libvpx: Add VP9 decoder.

source/libvpx/vpx/vpx_encoder.h

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 14 matching lines @@
  *
  */
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 #ifndef VPX_ENCODER_H
 #define VPX_ENCODER_H
 #include "vpx_codec.h"
 
-/*! Temporal Scalability: Maximum length of the sequence defining frame
- * layer membership
- */
+  /*! Temporal Scalability: Maximum length of the sequence defining frame
+   * layer membership
+   */
 #define VPX_TS_MAX_PERIODICITY 16
 
-/*! Temporal Scalability: Maximum number of coding layers */
+  /*! Temporal Scalability: Maximum number of coding layers */
 #define VPX_TS_MAX_LAYERS       5
 
-/*!\deprecated Use #VPX_TS_MAX_PERIODICITY instead. */
+  /*!\deprecated Use #VPX_TS_MAX_PERIODICITY instead. */
 #define MAX_PERIODICITY VPX_TS_MAX_PERIODICITY
 
-/*!\deprecated Use #VPX_TS_MAX_LAYERS instead. */
+  /*!\deprecated Use #VPX_TS_MAX_LAYERS instead. */
 #define MAX_LAYERS      VPX_TS_MAX_LAYERS
 
-    /*!\brief Current ABI version number
-     *
-     * \internal
-     * If this file is altered in any way that changes the ABI, this value
-     * must be bumped.  Examples include, but are not limited to, changing
-     * types, removing or reassigning enums, adding/removing/rearranging
-     * fields to structures
-     */
+  /*!\brief Current ABI version number
+   *
+   * \internal
+   * If this file is altered in any way that changes the ABI, this value
+   * must be bumped.  Examples include, but are not limited to, changing
+   * types, removing or reassigning enums, adding/removing/rearranging
+   * fields to structures
+   */
 #define VPX_ENCODER_ABI_VERSION (3 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/
 
 
-    /*! \brief Encoder capabilities bitfield
-     *
-     *  Each encoder advertises the capabilities it supports as part of its
-     *  ::vpx_codec_iface_t interface structure. Capabilities are extra
-     *  interfaces or functionality, and are not required to be supported
-     *  by an encoder.
-     *
-     *  The available flags are specified by VPX_CODEC_CAP_* defines.
-     */
+  /*! \brief Encoder capabilities bitfield
+   *
+   *  Each encoder advertises the capabilities it supports as part of its
+   *  ::vpx_codec_iface_t interface structure. Capabilities are extra
+   *  interfaces or functionality, and are not required to be supported
+   *  by an encoder.
+   *
+   *  The available flags are specified by VPX_CODEC_CAP_* defines.
+   */
 #define VPX_CODEC_CAP_PSNR  0x10000 /**< Can issue PSNR packets */
 
-    /*! Can output one partition at a time. Each partition is returned in its
-     *  own VPX_CODEC_CX_FRAME_PKT, with the FRAME_IS_FRAGMENT flag set for
-     *  every partition but the last. In this mode all frames are always
-     *  returned partition by partition.
-     */
+  /*! Can output one partition at a time. Each partition is returned in its
+   *  own VPX_CODEC_CX_FRAME_PKT, with the FRAME_IS_FRAGMENT flag set for
+   *  every partition but the last. In this mode all frames are always
+   *  returned partition by partition.
+   */
 #define VPX_CODEC_CAP_OUTPUT_PARTITION  0x20000
 
 
-    /*! \brief Initialization-time Feature Enabling
-     *
-     *  Certain codec features must be known at initialization time, to allow
-     *  for proper memory allocation.
-     *
-     *  The available flags are specified by VPX_CODEC_USE_* defines.
-     */
+  /*! \brief Initialization-time Feature Enabling
+   *
+   *  Certain codec features must be known at initialization time, to allow
+   *  for proper memory allocation.
+   *
+   *  The available flags are specified by VPX_CODEC_USE_* defines.
+   */
 #define VPX_CODEC_USE_PSNR  0x10000 /**< Calculate PSNR on each frame */
 #define VPX_CODEC_USE_OUTPUT_PARTITION  0x20000 /**< Make the encoder output one
-                                                     partition at a time. */
-
-
-    /*!\brief Generic fixed size buffer structure
-     *
-     * This structure is able to hold a reference to any fixed size buffer.
-     */
-    typedef struct vpx_fixed_buf
-    {
-        void          *buf; /**< Pointer to the data */
-        size_t         sz;  /**< Length of the buffer, in chars */
-    } vpx_fixed_buf_t; /**< alias for struct vpx_fixed_buf */
-
-
-    /*!\brief Time Stamp Type
-     *
-     * An integer, which when multiplied by the stream's time base, provides
-     * the absolute time of a sample.
-     */
-    typedef int64_t vpx_codec_pts_t;
-
-
-    /*!\brief Compressed Frame Flags
-     *
-     * This type represents a bitfield containing information about a compressed
-     * frame that may be useful to an application. The most significant 16 bits
-     * can be used by an algorithm to provide additional detail, for example to
-     * support frame types that are codec specific (MPEG-1 D-frames for example)
-     */
-    typedef uint32_t vpx_codec_frame_flags_t;
+  partition at a time. */
+
+
+  /*!\brief Generic fixed size buffer structure
+   *
+   * This structure is able to hold a reference to any fixed size buffer.
+   */
+  typedef struct vpx_fixed_buf {
+    void          *buf; /**< Pointer to the data */
+    size_t         sz;  /**< Length of the buffer, in chars */
+  } vpx_fixed_buf_t; /**< alias for struct vpx_fixed_buf */
+
+
+  /*!\brief Time Stamp Type
+   *
+   * An integer, which when multiplied by the stream's time base, provides
+   * the absolute time of a sample.
+   */
+  typedef int64_t vpx_codec_pts_t;
+
+
+  /*!\brief Compressed Frame Flags
+   *
+   * This type represents a bitfield containing information about a compressed
+   * frame that may be useful to an application. The most significant 16 bits
+   * can be used by an algorithm to provide additional detail, for example to
+   * support frame types that are codec specific (MPEG-1 D-frames for example)
+   */
+  typedef uint32_t vpx_codec_frame_flags_t;
 #define VPX_FRAME_IS_KEY       0x1 /**< frame is the start of a GOP */
 #define VPX_FRAME_IS_DROPPABLE 0x2 /**< frame can be dropped without affecting
-    the stream (no future frame depends on
-                this one) */
+  the stream (no future frame depends on
+              this one) */
 #define VPX_FRAME_IS_INVISIBLE 0x4 /**< frame should be decoded but will not
-    be shown */
+  be shown */
 #define VPX_FRAME_IS_FRAGMENT  0x8 /**< this is a fragment of the encoded
-    frame */
-
-    /*!\brief Error Resilient flags
-     *
-     * These flags define which error resilient features to enable in the
-     * encoder. The flags are specified through the
-     * vpx_codec_enc_cfg::g_error_resilient variable.
-     */
-    typedef uint32_t vpx_codec_er_flags_t;
+  frame */
+
+  /*!\brief Error Resilient flags
+   *
+   * These flags define which error resilient features to enable in the
+   * encoder. The flags are specified through the
+   * vpx_codec_enc_cfg::g_error_resilient variable.
+   */
+  typedef uint32_t vpx_codec_er_flags_t;
 #define VPX_ERROR_RESILIENT_DEFAULT     0x1 /**< Improve resiliency against
-                                                 losses of whole frames */
+  losses of whole frames */
 #define VPX_ERROR_RESILIENT_PARTITIONS  0x2 /**< The frame partitions are
-                                                 independently decodable by the
-                                                 bool decoder, meaning that
-                                                 partitions can be decoded even
-                                                 though earlier partitions have
-                                                 been lost. Note that intra
-                                                 predicition is still done over
-                                                 the partition boundary. */
-
-    /*!\brief Encoder output packet variants
-     *
-     * This enumeration lists the different kinds of data packets that can be
-     * returned by calls to vpx_codec_get_cx_data(). Algorithms \ref MAY
-     * extend this list to provide additional functionality.
-     */
-    enum vpx_codec_cx_pkt_kind
-    {
-        VPX_CODEC_CX_FRAME_PKT,    /**< Compressed video frame */
-        VPX_CODEC_STATS_PKT,       /**< Two-pass statistics for this frame */
-        VPX_CODEC_PSNR_PKT,        /**< PSNR statistics for this frame */
-        VPX_CODEC_CUSTOM_PKT = 256 /**< Algorithm extensions  */
-    };
-
-
-    /*!\brief Encoder output packet
-     *
-     * This structure contains the different kinds of output data the encoder
-     * may produce while compressing a frame.
-     */
-    typedef struct vpx_codec_cx_pkt
-    {
-        enum vpx_codec_cx_pkt_kind  kind; /**< packet variant */
-        union
-        {
-            struct
-            {
-                void                    *buf;      /**< compressed data buffer */
-                size_t                   sz;       /**< length of compressed data */
-                vpx_codec_pts_t          pts;      /**< time stamp to show frame
+  independently decodable by the
+  bool decoder, meaning that
+  partitions can be decoded even
+  though earlier partitions have
+  been lost. Note that intra
+  predicition is still done over
+  the partition boundary. */
+
+  /*!\brief Encoder output packet variants
+   *
+   * This enumeration lists the different kinds of data packets that can be
+   * returned by calls to vpx_codec_get_cx_data(). Algorithms \ref MAY
+   * extend this list to provide additional functionality.
+   */
+  enum vpx_codec_cx_pkt_kind {
+    VPX_CODEC_CX_FRAME_PKT,    /**< Compressed video frame */
+    VPX_CODEC_STATS_PKT,       /**< Two-pass statistics for this frame */
+    VPX_CODEC_PSNR_PKT,        /**< PSNR statistics for this frame */
+    VPX_CODEC_CUSTOM_PKT = 256 /**< Algorithm extensions  */
+  };
+
+
+  /*!\brief Encoder output packet
+   *
+   * This structure contains the different kinds of output data the encoder
+   * may produce while compressing a frame.
+   */
+  typedef struct vpx_codec_cx_pkt {
+    enum vpx_codec_cx_pkt_kind  kind; /**< packet variant */
+    union {
+      struct {
+        void                    *buf;      /**< compressed data buffer */
+        size_t                   sz;       /**< length of compressed data */
+        vpx_codec_pts_t          pts;      /**< time stamp to show frame
                                                     (in timebase units) */
-                unsigned long            duration; /**< duration to show frame
+        unsigned long            duration; /**< duration to show frame
                                                     (in timebase units) */
-                vpx_codec_frame_flags_t  flags;    /**< flags for this frame */
-                int                      partition_id; /**< the partition id
+        vpx_codec_frame_flags_t  flags;    /**< flags for this frame */
+        int                      partition_id; /**< the partition id
                                               defines the decoding order
                                               of the partitions. Only
                                               applicable when "output partition"
                                               mode is enabled. First partition
                                               has id 0.*/
 
-            } frame;  /**< data for compressed frame packet */
-            struct vpx_fixed_buf twopass_stats;  /**< data for two-pass packet */
-            struct vpx_psnr_pkt
-            {
-                unsigned int samples[4];  /**< Number of samples, total/y/u/v */
-                uint64_t     sse[4];      /**< sum squared error, total/y/u/v */
-                double       psnr[4];     /**< PSNR, total/y/u/v */
-            } psnr;                       /**< data for PSNR packet */
-            struct vpx_fixed_buf raw;     /**< data for arbitrary packets */
-
-            /* This packet size is fixed to allow codecs to extend this
-             * interface without having to manage storage for raw packets,
-             * i.e., if it's smaller than 128 bytes, you can store in the
-             * packet list directly.
-             */
-            char pad[128 - sizeof(enum vpx_codec_cx_pkt_kind)]; /**< fixed sz */
-        } data; /**< packet data */
-    } vpx_codec_cx_pkt_t; /**< alias for struct vpx_codec_cx_pkt */
-
-
-    /*!\brief Rational Number
-     *
-     * This structure holds a fractional value.
-     */
-    typedef struct vpx_rational
-    {
-        int num; /**< fraction numerator */
-        int den; /**< fraction denominator */
-    } vpx_rational_t; /**< alias for struct vpx_rational */
-
-
-    /*!\brief Multi-pass Encoding Pass */
-    enum vpx_enc_pass
-    {
-        VPX_RC_ONE_PASS,   /**< Single pass mode */
-        VPX_RC_FIRST_PASS, /**< First pass of multi-pass mode */
-        VPX_RC_LAST_PASS   /**< Final pass of multi-pass mode */
-    };
-
-
-    /*!\brief Rate control mode */
-    enum vpx_rc_mode
-    {
-        VPX_VBR, /**< Variable Bit Rate (VBR) mode */
-        VPX_CBR,  /**< Constant Bit Rate (CBR) mode */
-        VPX_CQ   /**< Constant Quality  (CQ)  mode */
-    };
-
-
-    /*!\brief Keyframe placement mode.
-     *
-     * This enumeration determines whether keyframes are placed automatically by
-     * the encoder or whether this behavior is disabled. Older releases of this
-     * SDK were implemented such that VPX_KF_FIXED meant keyframes were disabled.
-     * This name is confusing for this behavior, so the new symbols to be used
-     * are VPX_KF_AUTO and VPX_KF_DISABLED.
-     */
-    enum vpx_kf_mode
-    {
-        VPX_KF_FIXED, /**< deprecated, implies VPX_KF_DISABLED */
-        VPX_KF_AUTO,  /**< Encoder determines optimal placement automatically */
-        VPX_KF_DISABLED = 0 /**< Encoder does not place keyframes. */
-    };
-
-
-    /*!\brief Encoded Frame Flags
-     *
-     * This type indicates a bitfield to be passed to vpx_codec_encode(), defining
-     * per-frame boolean values. By convention, bits common to all codecs will be
-     * named VPX_EFLAG_*, and bits specific to an algorithm will be named
-     * /algo/_eflag_*. The lower order 16 bits are reserved for common use.
-     */
-    typedef long vpx_enc_frame_flags_t;
+      } frame;  /**< data for compressed frame packet */
+      struct vpx_fixed_buf twopass_stats;  /**< data for two-pass packet */
+      struct vpx_psnr_pkt {
+        unsigned int samples[4];  /**< Number of samples, total/y/u/v */
+        uint64_t     sse[4];      /**< sum squared error, total/y/u/v */
+        double       psnr[4];     /**< PSNR, total/y/u/v */
+      } psnr;                       /**< data for PSNR packet */
+      struct vpx_fixed_buf raw;     /**< data for arbitrary packets */
+
+      /* This packet size is fixed to allow codecs to extend this
+       * interface without having to manage storage for raw packets,
+       * i.e., if it's smaller than 128 bytes, you can store in the
+       * packet list directly.
+       */
+      char pad[128 - sizeof(enum vpx_codec_cx_pkt_kind)]; /**< fixed sz */
+    } data; /**< packet data */
+  } vpx_codec_cx_pkt_t; /**< alias for struct vpx_codec_cx_pkt */
+
+
+  /*!\brief Rational Number
+   *
+   * This structure holds a fractional value.
+   */
+  typedef struct vpx_rational {
+    int num; /**< fraction numerator */
+    int den; /**< fraction denominator */
+  } vpx_rational_t; /**< alias for struct vpx_rational */
+
+
+  /*!\brief Multi-pass Encoding Pass */
+  enum vpx_enc_pass {
+    VPX_RC_ONE_PASS,   /**< Single pass mode */
+    VPX_RC_FIRST_PASS, /**< First pass of multi-pass mode */
+    VPX_RC_LAST_PASS   /**< Final pass of multi-pass mode */
+  };
+
+
+  /*!\brief Rate control mode */
+  enum vpx_rc_mode {
+    VPX_VBR, /**< Variable Bit Rate (VBR) mode */
+    VPX_CBR,  /**< Constant Bit Rate (CBR) mode */
+    VPX_CQ   /**< Constant Quality  (CQ)  mode */
+  };
+
+
+  /*!\brief Keyframe placement mode.
+   *
+   * This enumeration determines whether keyframes are placed automatically by
+   * the encoder or whether this behavior is disabled. Older releases of this
+   * SDK were implemented such that VPX_KF_FIXED meant keyframes were disabled.
+   * This name is confusing for this behavior, so the new symbols to be used
+   * are VPX_KF_AUTO and VPX_KF_DISABLED.
+   */
+  enum vpx_kf_mode {
+    VPX_KF_FIXED, /**< deprecated, implies VPX_KF_DISABLED */
+    VPX_KF_AUTO,  /**< Encoder determines optimal placement automatically */
+    VPX_KF_DISABLED = 0 /**< Encoder does not place keyframes. */
+  };
+
+
+  /*!\brief Encoded Frame Flags
+   *
+   * This type indicates a bitfield to be passed to vpx_codec_encode(), defining
+   * per-frame boolean values. By convention, bits common to all codecs will be
+   * named VPX_EFLAG_*, and bits specific to an algorithm will be named
+   * /algo/_eflag_*. The lower order 16 bits are reserved for common use.
+   */
+  typedef long vpx_enc_frame_flags_t;
 #define VPX_EFLAG_FORCE_KF (1<<0)  /**< Force this frame to be a keyframe */
 
 
-    /*!\brief Encoder configuration structure
-     *
-     * This structure contains the encoder settings that have common representations
-     * across all codecs. This doesn't imply that all codecs support all features,
-     * however.
-     */
-    typedef struct vpx_codec_enc_cfg
-    {
-        /*
-         * generic settings (g)
-         */
-
-        /*!\brief Algorithm specific "usage" value
-         *
-         * Algorithms may define multiple values for usage, which may convey the
-         * intent of how the application intends to use the stream. If this value
-         * is non-zero, consult the documentation for the codec to determine its
-         * meaning.
-         */
-        unsigned int           g_usage;
-
-
-        /*!\brief Maximum number of threads to use
-         *
-         * For multi-threaded implementations, use no more than this number of
-         * threads. The codec may use fewer threads than allowed. The value
-         * 0 is equivalent to the value 1.
-         */
-        unsigned int           g_threads;
-
-
-        /*!\brief Bitstream profile to use
-         *
-         * Some codecs support a notion of multiple bitstream profiles. Typically
-         * this maps to a set of features that are turned on or off. Often the
-         * profile to use is determined by the features of the intended decoder.
-         * Consult the documentation for the codec to determine the valid values
-         * for this parameter, or set to zero for a sane default.
-         */
-        unsigned int           g_profile;  /**< profile of bitstream to use */
-
-
-
-        /*!\brief Width of the frame
-         *
-         * This value identifies the presentation resolution of the frame,
-         * in pixels. Note that the frames passed as input to the encoder must
-         * have this resolution. Frames will be presented by the decoder in this
-         * resolution, independent of any spatial resampling the encoder may do.
-         */
-        unsigned int           g_w;
-
-
-        /*!\brief Height of the frame
-         *
-         * This value identifies the presentation resolution of the frame,
-         * in pixels. Note that the frames passed as input to the encoder must
-         * have this resolution. Frames will be presented by the decoder in this
-         * resolution, independent of any spatial resampling the encoder may do.
-         */
-        unsigned int           g_h;
-
-
-        /*!\brief Stream timebase units
-         *
-         * Indicates the smallest interval of time, in seconds, used by the stream.
-         * For fixed frame rate material, or variable frame rate material where
-         * frames are timed at a multiple of a given clock (ex: video capture),
-         * the \ref RECOMMENDED method is to set the timebase to the reciprocal
-         * of the frame rate (ex: 1001/30000 for 29.970 Hz NTSC). This allows the
-         * pts to correspond to the frame number, which can be handy. For
-         * re-encoding video from containers with absolute time timestamps, the
-         * \ref RECOMMENDED method is to set the timebase to that of the parent
-         * container or multimedia framework (ex: 1/1000 for ms, as in FLV).
-         */
-        struct vpx_rational    g_timebase;
-
-
-        /*!\brief Enable error resilient modes.
-         *
-         * The error resilient bitfield indicates to the encoder which features
-         * it should enable to take measures for streaming over lossy or noisy
-         * links.
-         */
-        vpx_codec_er_flags_t   g_error_resilient;
-
-
-        /*!\brief Multi-pass Encoding Mode
-         *
-         * This value should be set to the current phase for multi-pass encoding.
-         * For single pass, set to #VPX_RC_ONE_PASS.
-         */
-        enum vpx_enc_pass      g_pass;
-
-
-        /*!\brief Allow lagged encoding
-         *
-         * If set, this value allows the encoder to consume a number of input
-         * frames before producing output frames. This allows the encoder to
-         * base decisions for the current frame on future frames. This does
-         * increase the latency of the encoding pipeline, so it is not appropriate
-         * in all situations (ex: realtime encoding).
-         *
-         * Note that this is a maximum value -- the encoder may produce frames
-         * sooner than the given limit. Set this value to 0 to disable this
-         * feature.
-         */
-        unsigned int           g_lag_in_frames;
-
-
-        /*
-         * rate control settings (rc)
-         */
-
-        /*!\brief Temporal resampling configuration, if supported by the codec.
-         *
-         * Temporal resampling allows the codec to "drop" frames as a strategy to
-         * meet its target data rate. This can cause temporal discontinuities in
-         * the encoded video, which may appear as stuttering during playback. This
-         * trade-off is often acceptable, but for many applications is not. It can
-         * be disabled in these cases.
-         *
-         * Note that not all codecs support this feature. All vpx VPx codecs do.
-         * For other codecs, consult the documentation for that algorithm.
-         *
-         * This threshold is described as a percentage of the target data buffer.
-         * When the data buffer falls below this percentage of fullness, a
-         * dropped frame is indicated. Set the threshold to zero (0) to disable
-         * this feature.
-         */
-        unsigned int           rc_dropframe_thresh;
-
-
-        /*!\brief Enable/disable spatial resampling, if supported by the codec.
-         *
-         * Spatial resampling allows the codec to compress a lower resolution
-         * version of the frame, which is then upscaled by the encoder to the
-         * correct presentation resolution. This increases visual quality at
-         * low data rates, at the expense of CPU time on the encoder/decoder.
-         */
-        unsigned int           rc_resize_allowed;
-
-
-        /*!\brief Spatial resampling up watermark.
-         *
-         * This threshold is described as a percentage of the target data buffer.
-         * When the data buffer rises above this percentage of fullness, the
-         * encoder will step up to a higher resolution version of the frame.
-         */
-        unsigned int           rc_resize_up_thresh;
-
-
-        /*!\brief Spatial resampling down watermark.
-         *
-         * This threshold is described as a percentage of the target data buffer.
-         * When the data buffer falls below this percentage of fullness, the
-         * encoder will step down to a lower resolution version of the frame.
-         */
-        unsigned int           rc_resize_down_thresh;
-
-
-        /*!\brief Rate control algorithm to use.
-         *
-         * Indicates whether the end usage of this stream is to be streamed over
-         * a bandwidth constrained link, indicating that Constant Bit Rate (CBR)
-         * mode should be used, or whether it will be played back on a high
-         * bandwidth link, as from a local disk, where higher variations in
-         * bitrate are acceptable.
-         */
-        enum vpx_rc_mode       rc_end_usage;
-
-
-        /*!\brief Two-pass stats buffer.
-         *
-         * A buffer containing all of the stats packets produced in the first
-         * pass, concatenated.
-         */
-        struct vpx_fixed_buf   rc_twopass_stats_in;
-
-
-        /*!\brief Target data rate
-         *
-         * Target bandwidth to use for this stream, in kilobits per second.
-         */
-        unsigned int           rc_target_bitrate;
-
-
-        /*
-         * quantizer settings
-         */
-
-
-        /*!\brief Minimum (Best Quality) Quantizer
-         *
-         * The quantizer is the most direct control over the quality of the
-         * encoded image. The range of valid values for the quantizer is codec
-         * specific. Consult the documentation for the codec to determine the
-         * values to use. To determine the range programmatically, call
-         * vpx_codec_enc_config_default() with a usage value of 0.
-         */
-        unsigned int           rc_min_quantizer;
-
-
-        /*!\brief Maximum (Worst Quality) Quantizer
-         *
-         * The quantizer is the most direct control over the quality of the
-         * encoded image. The range of valid values for the quantizer is codec
-         * specific. Consult the documentation for the codec to determine the
-         * values to use. To determine the range programmatically, call
-         * vpx_codec_enc_config_default() with a usage value of 0.
-         */
-        unsigned int           rc_max_quantizer;
-
-
-        /*
-         * bitrate tolerance
-         */
-
-
-        /*!\brief Rate control adaptation undershoot control
-         *
-         * This value, expressed as a percentage of the target bitrate,
-         * controls the maximum allowed adaptation speed of the codec.
-         * This factor controls the maximum amount of bits that can
-         * be subtracted from the target bitrate in order to compensate
-         * for prior overshoot.
-         *
-         * Valid values in the range 0-1000.
-         */
-        unsigned int           rc_undershoot_pct;
-
-
-        /*!\brief Rate control adaptation overshoot control
-         *
-         * This value, expressed as a percentage of the target bitrate,
-         * controls the maximum allowed adaptation speed of the codec.
-         * This factor controls the maximum amount of bits that can
-         * be added to the target bitrate in order to compensate for
-         * prior undershoot.
-         *
-         * Valid values in the range 0-1000.
-         */
-        unsigned int           rc_overshoot_pct;
-
-
-        /*
-         * decoder buffer model parameters
-         */
-
-
-        /*!\brief Decoder Buffer Size
-         *
-         * This value indicates the amount of data that may be buffered by the
-         * decoding application. Note that this value is expressed in units of
-         * time (milliseconds). For example, a value of 5000 indicates that the
-         * client will buffer (at least) 5000ms worth of encoded data. Use the
-         * target bitrate (#rc_target_bitrate) to convert to bits/bytes, if
-         * necessary.
-         */
-        unsigned int           rc_buf_sz;
-
-
-        /*!\brief Decoder Buffer Initial Size
-         *
-         * This value indicates the amount of data that will be buffered by the
-         * decoding application prior to beginning playback. This value is
-         * expressed in units of time (milliseconds). Use the target bitrate
-         * (#rc_target_bitrate) to convert to bits/bytes, if necessary.
-         */
-        unsigned int           rc_buf_initial_sz;
-
-
-        /*!\brief Decoder Buffer Optimal Size
-         *
-         * This value indicates the amount of data that the encoder should try
-         * to maintain in the decoder's buffer. This value is expressed in units
-         * of time (milliseconds). Use the target bitrate (#rc_target_bitrate)
-         * to convert to bits/bytes, if necessary.
-         */
-        unsigned int           rc_buf_optimal_sz;
-
-
-        /*
-         * 2 pass rate control parameters
-         */
-
-
-        /*!\brief Two-pass mode CBR/VBR bias
-         *
-         * Bias, expressed on a scale of 0 to 100, for determining target size
-         * for the current frame. The value 0 indicates the optimal CBR mode
-         * value should be used. The value 100 indicates the optimal VBR mode
-         * value should be used. Values in between indicate which way the
-         * encoder should "lean."
-         */
-        unsigned int           rc_2pass_vbr_bias_pct;       /**< RC mode bias between CBR and VBR(0-100: 0->CBR, 100->VBR)   */
-
-
-        /*!\brief Two-pass mode per-GOP minimum bitrate
-         *
-         * This value, expressed as a percentage of the target bitrate, indicates
-         * the minimum bitrate to be used for a single GOP (aka "section")
-         */
-        unsigned int           rc_2pass_vbr_minsection_pct;
-
-
-        /*!\brief Two-pass mode per-GOP maximum bitrate
-         *
-         * This value, expressed as a percentage of the target bitrate, indicates
-         * the maximum bitrate to be used for a single GOP (aka "section")
-         */
-        unsigned int           rc_2pass_vbr_maxsection_pct;
-
-
-        /*
-         * keyframing settings (kf)
-         */
-
-        /*!\brief Keyframe placement mode
-         *
-         * This value indicates whether the encoder should place keyframes at a
-         * fixed interval, or determine the optimal placement automatically
-         * (as governed by the #kf_min_dist and #kf_max_dist parameters)
-         */
-        enum vpx_kf_mode       kf_mode;
-
-
-        /*!\brief Keyframe minimum interval
-         *
-         * This value, expressed as a number of frames, prevents the encoder from
-         * placing a keyframe nearer than kf_min_dist to the previous keyframe. At
-         * least kf_min_dist frames non-keyframes will be coded before the next
-         * keyframe. Set kf_min_dist equal to kf_max_dist for a fixed interval.
-         */
-        unsigned int           kf_min_dist;
-
-
-        /*!\brief Keyframe maximum interval
-         *
-         * This value, expressed as a number of frames, forces the encoder to code
-         * a keyframe if one has not been coded in the last kf_max_dist frames.
-         * A value of 0 implies all frames will be keyframes. Set kf_min_dist
-         * equal to kf_max_dist for a fixed interval.
-         */
-        unsigned int           kf_max_dist;
-
-        /*
-         * Temporal scalability settings (ts)
-         */
-
-        /*!\brief Number of coding layers
-         *
-         * This value specifies the number of coding layers to be used.
-         */
-        unsigned int           ts_number_layers;
-
-        /*!\brief Target bitrate for each layer
-         *
-         * These values specify the target coding bitrate for each coding layer.
-         */
-        unsigned int           ts_target_bitrate[VPX_TS_MAX_LAYERS];
-
-        /*!\brief Frame rate decimation factor for each layer
-         *
-         * These values specify the frame rate decimation factors to apply
-         * to each layer.
-         */
-        unsigned int           ts_rate_decimator[VPX_TS_MAX_LAYERS];
-
-        /*!\brief Length of the sequence defining frame layer membership
-         *
-         * This value specifies the length of the sequence that defines the
-         * membership of frames to layers. For example, if ts_periodicity=8 then
-         * frames are assigned to coding layers with a repeated sequence of
-         * length 8.
-         */
-        unsigned int           ts_periodicity;
-
-        /*!\brief Template defining the membership of frames to coding layers
-         *
-         * This array defines the membership of frames to coding layers. For a
-         * 2-layer encoding that assigns even numbered frames to one layer (0)
-         * and odd numbered frames to a second layer (1) with ts_periodicity=8,
-         * then ts_layer_id = (0,1,0,1,0,1,0,1).
-         */
-        unsigned int           ts_layer_id[VPX_TS_MAX_PERIODICITY];
-    } vpx_codec_enc_cfg_t; /**< alias for struct vpx_codec_enc_cfg */
-
-
-    /*!\brief Initialize an encoder instance
-     *
-     * Initializes a encoder context using the given interface. Applications
-     * should call the vpx_codec_enc_init convenience macro instead of this
-     * function directly, to ensure that the ABI version number parameter
-     * is properly initialized.
-     *
-     * If the library was configured with --disable-multithread, this call
-     * is not thread safe and should be guarded with a lock if being used
-     * in a multithreaded context.
-     *
-     * In XMA mode (activated by setting VPX_CODEC_USE_XMA in the flags
-     * parameter), the storage pointed to by the cfg parameter must be
-     * kept readable and stable until all memory maps have been set.
-     *
-     * \param[in]    ctx     Pointer to this instance's context.
-     * \param[in]    iface   Pointer to the algorithm interface to use.
-     * \param[in]    cfg     Configuration to use, if known. May be NULL.
-     * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
-     * \param[in]    ver     ABI version number. Must be set to
-     *                       VPX_ENCODER_ABI_VERSION
-     * \retval #VPX_CODEC_OK
-     *     The decoder algorithm initialized.
-     * \retval #VPX_CODEC_MEM_ERROR
-     *     Memory allocation failed.
-     */
-    vpx_codec_err_t vpx_codec_enc_init_ver(vpx_codec_ctx_t      *ctx,
-                                           vpx_codec_iface_t    *iface,
-                                           vpx_codec_enc_cfg_t  *cfg,
-                                           vpx_codec_flags_t     flags,
-                                           int                   ver);
-
-
-    /*!\brief Convenience macro for vpx_codec_enc_init_ver()
-     *
-     * Ensures the ABI version parameter is properly set.
-     */
+  /*!\brief Encoder configuration structure
+   *
+   * This structure contains the encoder settings that have common representations
+   * across all codecs. This doesn't imply that all codecs support all features,
+   * however.
+   */
+  typedef struct vpx_codec_enc_cfg {
+    /*
+     * generic settings (g)
+     */
+
+    /*!\brief Algorithm specific "usage" value
+     *
+     * Algorithms may define multiple values for usage, which may convey the
+     * intent of how the application intends to use the stream. If this value
+     * is non-zero, consult the documentation for the codec to determine its
+     * meaning.
+     */
+    unsigned int           g_usage;
+
+
+    /*!\brief Maximum number of threads to use
+     *
+     * For multi-threaded implementations, use no more than this number of
+     * threads. The codec may use fewer threads than allowed. The value
+     * 0 is equivalent to the value 1.
+     */
+    unsigned int           g_threads;
+
+
+    /*!\brief Bitstream profile to use
+     *
+     * Some codecs support a notion of multiple bitstream profiles. Typically
+     * this maps to a set of features that are turned on or off. Often the
+     * profile to use is determined by the features of the intended decoder.
+     * Consult the documentation for the codec to determine the valid values
+     * for this parameter, or set to zero for a sane default.
+     */
+    unsigned int           g_profile;  /**< profile of bitstream to use */
+
+
+
+    /*!\brief Width of the frame
+     *
+     * This value identifies the presentation resolution of the frame,
+     * in pixels. Note that the frames passed as input to the encoder must
+     * have this resolution. Frames will be presented by the decoder in this
+     * resolution, independent of any spatial resampling the encoder may do.
+     */
+    unsigned int           g_w;
+
+
+    /*!\brief Height of the frame
+     *
+     * This value identifies the presentation resolution of the frame,
+     * in pixels. Note that the frames passed as input to the encoder must
+     * have this resolution. Frames will be presented by the decoder in this
+     * resolution, independent of any spatial resampling the encoder may do.
+     */
+    unsigned int           g_h;
+
+
+    /*!\brief Stream timebase units
+     *
+     * Indicates the smallest interval of time, in seconds, used by the stream.
+     * For fixed frame rate material, or variable frame rate material where
+     * frames are timed at a multiple of a given clock (ex: video capture),
+     * the \ref RECOMMENDED method is to set the timebase to the reciprocal
+     * of the frame rate (ex: 1001/30000 for 29.970 Hz NTSC). This allows the
+     * pts to correspond to the frame number, which can be handy. For
+     * re-encoding video from containers with absolute time timestamps, the
+     * \ref RECOMMENDED method is to set the timebase to that of the parent
+     * container or multimedia framework (ex: 1/1000 for ms, as in FLV).
+     */
+    struct vpx_rational    g_timebase;
+
+
+    /*!\brief Enable error resilient modes.
+     *
+     * The error resilient bitfield indicates to the encoder which features
+     * it should enable to take measures for streaming over lossy or noisy
+     * links.
+     */
+    vpx_codec_er_flags_t   g_error_resilient;
+
+
+    /*!\brief Multi-pass Encoding Mode
+     *
+     * This value should be set to the current phase for multi-pass encoding.
+     * For single pass, set to #VPX_RC_ONE_PASS.
+     */
+    enum vpx_enc_pass      g_pass;
+
+
+    /*!\brief Allow lagged encoding
+     *
+     * If set, this value allows the encoder to consume a number of input
+     * frames before producing output frames. This allows the encoder to
+     * base decisions for the current frame on future frames. This does
+     * increase the latency of the encoding pipeline, so it is not appropriate
+     * in all situations (ex: realtime encoding).
+     *
+     * Note that this is a maximum value -- the encoder may produce frames
+     * sooner than the given limit. Set this value to 0 to disable this
+     * feature.
+     */
+    unsigned int           g_lag_in_frames;
+
+
+    /*
+     * rate control settings (rc)
+     */
+
+    /*!\brief Temporal resampling configuration, if supported by the codec.
+     *
+     * Temporal resampling allows the codec to "drop" frames as a strategy to
+     * meet its target data rate. This can cause temporal discontinuities in
+     * the encoded video, which may appear as stuttering during playback. This
+     * trade-off is often acceptable, but for many applications is not. It can
+     * be disabled in these cases.
+     *
+     * Note that not all codecs support this feature. All vpx VPx codecs do.
+     * For other codecs, consult the documentation for that algorithm.
+     *
+     * This threshold is described as a percentage of the target data buffer.
+     * When the data buffer falls below this percentage of fullness, a
+     * dropped frame is indicated. Set the threshold to zero (0) to disable
+     * this feature.
+     */
+    unsigned int           rc_dropframe_thresh;
+
+
+    /*!\brief Enable/disable spatial resampling, if supported by the codec.
+     *
+     * Spatial resampling allows the codec to compress a lower resolution
+     * version of the frame, which is then upscaled by the encoder to the
+     * correct presentation resolution. This increases visual quality at
+     * low data rates, at the expense of CPU time on the encoder/decoder.
+     */
+    unsigned int           rc_resize_allowed;
+
+
+    /*!\brief Spatial resampling up watermark.
+     *
+     * This threshold is described as a percentage of the target data buffer.
+     * When the data buffer rises above this percentage of fullness, the
+     * encoder will step up to a higher resolution version of the frame.
+     */
+    unsigned int           rc_resize_up_thresh;
+
+
+    /*!\brief Spatial resampling down watermark.
+     *
+     * This threshold is described as a percentage of the target data buffer.
+     * When the data buffer falls below this percentage of fullness, the
+     * encoder will step down to a lower resolution version of the frame.
+     */
+    unsigned int           rc_resize_down_thresh;
+
+
+    /*!\brief Rate control algorithm to use.
+     *
+     * Indicates whether the end usage of this stream is to be streamed over
+     * a bandwidth constrained link, indicating that Constant Bit Rate (CBR)
+     * mode should be used, or whether it will be played back on a high
+     * bandwidth link, as from a local disk, where higher variations in
+     * bitrate are acceptable.
+     */
+    enum vpx_rc_mode       rc_end_usage;
+
+
+    /*!\brief Two-pass stats buffer.
+     *
+     * A buffer containing all of the stats packets produced in the first
+     * pass, concatenated.
+     */
+    struct vpx_fixed_buf   rc_twopass_stats_in;
+
+
+    /*!\brief Target data rate
+     *
+     * Target bandwidth to use for this stream, in kilobits per second.
+     */
+    unsigned int           rc_target_bitrate;
+
+
+    /*
+     * quantizer settings
+     */
+
+
+    /*!\brief Minimum (Best Quality) Quantizer
+     *
+     * The quantizer is the most direct control over the quality of the
+     * encoded image. The range of valid values for the quantizer is codec
+     * specific. Consult the documentation for the codec to determine the
+     * values to use. To determine the range programmatically, call
+     * vpx_codec_enc_config_default() with a usage value of 0.
+     */
+    unsigned int           rc_min_quantizer;
+
+
+    /*!\brief Maximum (Worst Quality) Quantizer
+     *
+     * The quantizer is the most direct control over the quality of the
+     * encoded image. The range of valid values for the quantizer is codec
+     * specific. Consult the documentation for the codec to determine the
+     * values to use. To determine the range programmatically, call
+     * vpx_codec_enc_config_default() with a usage value of 0.
+     */
+    unsigned int           rc_max_quantizer;
+
+
+    /*
+     * bitrate tolerance
+     */
+
+
+    /*!\brief Rate control adaptation undershoot control
+     *
+     * This value, expressed as a percentage of the target bitrate,
+     * controls the maximum allowed adaptation speed of the codec.
+     * This factor controls the maximum amount of bits that can
+     * be subtracted from the target bitrate in order to compensate
+     * for prior overshoot.
+     *
+     * Valid values in the range 0-1000.
+     */
+    unsigned int           rc_undershoot_pct;
+
+
+    /*!\brief Rate control adaptation overshoot control
+     *
+     * This value, expressed as a percentage of the target bitrate,
+     * controls the maximum allowed adaptation speed of the codec.
+     * This factor controls the maximum amount of bits that can
+     * be added to the target bitrate in order to compensate for
+     * prior undershoot.
+     *
+     * Valid values in the range 0-1000.
+     */
+    unsigned int           rc_overshoot_pct;
+
+
+    /*
+     * decoder buffer model parameters
+     */
+
+
+    /*!\brief Decoder Buffer Size
+     *
+     * This value indicates the amount of data that may be buffered by the
+     * decoding application. Note that this value is expressed in units of
+     * time (milliseconds). For example, a value of 5000 indicates that the
+     * client will buffer (at least) 5000ms worth of encoded data. Use the
+     * target bitrate (#rc_target_bitrate) to convert to bits/bytes, if
+     * necessary.
+     */
+    unsigned int           rc_buf_sz;
+
+
+    /*!\brief Decoder Buffer Initial Size
+     *
+     * This value indicates the amount of data that will be buffered by the
+     * decoding application prior to beginning playback. This value is
+     * expressed in units of time (milliseconds). Use the target bitrate
+     * (#rc_target_bitrate) to convert to bits/bytes, if necessary.
+     */
+    unsigned int           rc_buf_initial_sz;
+
+
+    /*!\brief Decoder Buffer Optimal Size
+     *
+     * This value indicates the amount of data that the encoder should try
+     * to maintain in the decoder's buffer. This value is expressed in units
+     * of time (milliseconds). Use the target bitrate (#rc_target_bitrate)
+     * to convert to bits/bytes, if necessary.
+     */
+    unsigned int           rc_buf_optimal_sz;
+
+
+    /*
+     * 2 pass rate control parameters
+     */
+
+
+    /*!\brief Two-pass mode CBR/VBR bias
+     *
+     * Bias, expressed on a scale of 0 to 100, for determining target size
+     * for the current frame. The value 0 indicates the optimal CBR mode
+     * value should be used. The value 100 indicates the optimal VBR mode
+     * value should be used. Values in between indicate which way the
+     * encoder should "lean."
+     */
+    unsigned int           rc_2pass_vbr_bias_pct;       /**< RC mode bias between CBR and VBR(0-100: 0->CBR, 100->VBR)   */
+
+
+    /*!\brief Two-pass mode per-GOP minimum bitrate
+     *
+     * This value, expressed as a percentage of the target bitrate, indicates
+     * the minimum bitrate to be used for a single GOP (aka "section")
+     */
+    unsigned int           rc_2pass_vbr_minsection_pct;
+
+
+    /*!\brief Two-pass mode per-GOP maximum bitrate
+     *
+     * This value, expressed as a percentage of the target bitrate, indicates
+     * the maximum bitrate to be used for a single GOP (aka "section")
+     */
+    unsigned int           rc_2pass_vbr_maxsection_pct;
+
+
+    /*
+     * keyframing settings (kf)
+     */
+
+    /*!\brief Keyframe placement mode
+     *
+     * This value indicates whether the encoder should place keyframes at a
+     * fixed interval, or determine the optimal placement automatically
+     * (as governed by the #kf_min_dist and #kf_max_dist parameters)
+     */
+    enum vpx_kf_mode       kf_mode;
+
+
+    /*!\brief Keyframe minimum interval
+     *
+     * This value, expressed as a number of frames, prevents the encoder from
+     * placing a keyframe nearer than kf_min_dist to the previous keyframe. At
+     * least kf_min_dist frames non-keyframes will be coded before the next
+     * keyframe. Set kf_min_dist equal to kf_max_dist for a fixed interval.
+     */
+    unsigned int           kf_min_dist;
+
+
+    /*!\brief Keyframe maximum interval
+     *
+     * This value, expressed as a number of frames, forces the encoder to code
+     * a keyframe if one has not been coded in the last kf_max_dist frames.
+     * A value of 0 implies all frames will be keyframes. Set kf_min_dist
+     * equal to kf_max_dist for a fixed interval.
+     */
+    unsigned int           kf_max_dist;
+
+    /*
+     * Temporal scalability settings (ts)
+     */
+
+    /*!\brief Number of coding layers
+     *
+     * This value specifies the number of coding layers to be used.
+     */
+    unsigned int           ts_number_layers;
+
+    /*!\brief Target bitrate for each layer
+     *
+     * These values specify the target coding bitrate for each coding layer.
+     */
+    unsigned int           ts_target_bitrate[VPX_TS_MAX_LAYERS];
+
+    /*!\brief Frame rate decimation factor for each layer
+     *
+     * These values specify the frame rate decimation factors to apply
+     * to each layer.
+     */
+    unsigned int           ts_rate_decimator[VPX_TS_MAX_LAYERS];
+
+    /*!\brief Length of the sequence defining frame layer membership
+     *
+     * This value specifies the length of the sequence that defines the
+     * membership of frames to layers. For example, if ts_periodicity=8 then
+     * frames are assigned to coding layers with a repeated sequence of
+     * length 8.
+     */
+    unsigned int           ts_periodicity;
+
+    /*!\brief Template defining the membership of frames to coding layers
+     *
+     * This array defines the membership of frames to coding layers. For a
+     * 2-layer encoding that assigns even numbered frames to one layer (0)
+     * and odd numbered frames to a second layer (1) with ts_periodicity=8,
+     * then ts_layer_id = (0,1,0,1,0,1,0,1).
+     */
+    unsigned int           ts_layer_id[VPX_TS_MAX_PERIODICITY];
+  } vpx_codec_enc_cfg_t; /**< alias for struct vpx_codec_enc_cfg */
+
+
+  /*!\brief Initialize an encoder instance
+   *
+   * Initializes a encoder context using the given interface. Applications
+   * should call the vpx_codec_enc_init convenience macro instead of this
+   * function directly, to ensure that the ABI version number parameter
+   * is properly initialized.
+   *
+   * If the library was configured with --disable-multithread, this call
+   * is not thread safe and should be guarded with a lock if being used
+   * in a multithreaded context.
+   *
+   * In XMA mode (activated by setting VPX_CODEC_USE_XMA in the flags
+   * parameter), the storage pointed to by the cfg parameter must be
+   * kept readable and stable until all memory maps have been set.
+   *
+   * \param[in]    ctx     Pointer to this instance's context.
+   * \param[in]    iface   Pointer to the algorithm interface to use.
+   * \param[in]    cfg     Configuration to use, if known. May be NULL.
+   * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
+   * \param[in]    ver     ABI version number. Must be set to
+   *                       VPX_ENCODER_ABI_VERSION
+   * \retval #VPX_CODEC_OK
+   *     The decoder algorithm initialized.
+   * \retval #VPX_CODEC_MEM_ERROR
+   *     Memory allocation failed.
+   */
+  vpx_codec_err_t vpx_codec_enc_init_ver(vpx_codec_ctx_t      *ctx,
+                                         vpx_codec_iface_t    *iface,
+                                         vpx_codec_enc_cfg_t  *cfg,
+                                         vpx_codec_flags_t     flags,
+                                         int                   ver);
+
+
+  /*!\brief Convenience macro for vpx_codec_enc_init_ver()
+   *
+   * Ensures the ABI version parameter is properly set.
+   */
 #define vpx_codec_enc_init(ctx, iface, cfg, flags) \
-    vpx_codec_enc_init_ver(ctx, iface, cfg, flags, VPX_ENCODER_ABI_VERSION)
-
-
-    /*!\brief Initialize multi-encoder instance
-     *
-     * Initializes multi-encoder context using the given interface.
-     * Applications should call the vpx_codec_enc_init_multi convenience macro
-     * instead of this function directly, to ensure that the ABI version number
-     * parameter is properly initialized.
-     *
-     * In XMA mode (activated by setting VPX_CODEC_USE_XMA in the flags
-     * parameter), the storage pointed to by the cfg parameter must be
-     * kept readable and stable until all memory maps have been set.
-     *
-     * \param[in]    ctx     Pointer to this instance's context.
-     * \param[in]    iface   Pointer to the algorithm interface to use.
-     * \param[in]    cfg     Configuration to use, if known. May be NULL.
-     * \param[in]    num_enc Total number of encoders.
-     * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
-     * \param[in]    dsf     Pointer to down-sampling factors.
-     * \param[in]    ver     ABI version number. Must be set to
-     *                       VPX_ENCODER_ABI_VERSION
-     * \retval #VPX_CODEC_OK
-     *     The decoder algorithm initialized.
-     * \retval #VPX_CODEC_MEM_ERROR
-     *     Memory allocation failed.
-     */
-    vpx_codec_err_t vpx_codec_enc_init_multi_ver(vpx_codec_ctx_t      *ctx,
-                                                 vpx_codec_iface_t    *iface,
-                                                 vpx_codec_enc_cfg_t  *cfg,
-                                                 int                   num_enc,
-                                                 vpx_codec_flags_t     flags,
-                                                 vpx_rational_t       *dsf,
-                                                 int                   ver);
-
-
-    /*!\brief Convenience macro for vpx_codec_enc_init_multi_ver()
-     *
-     * Ensures the ABI version parameter is properly set.
-     */
+  vpx_codec_enc_init_ver(ctx, iface, cfg, flags, VPX_ENCODER_ABI_VERSION)
+
+
+  /*!\brief Initialize multi-encoder instance
+   *
+   * Initializes multi-encoder context using the given interface.
+   * Applications should call the vpx_codec_enc_init_multi convenience macro
+   * instead of this function directly, to ensure that the ABI version number
+   * parameter is properly initialized.
+   *
+   * In XMA mode (activated by setting VPX_CODEC_USE_XMA in the flags
+   * parameter), the storage pointed to by the cfg parameter must be
+   * kept readable and stable until all memory maps have been set.
+   *
+   * \param[in]    ctx     Pointer to this instance's context.
+   * \param[in]    iface   Pointer to the algorithm interface to use.
+   * \param[in]    cfg     Configuration to use, if known. May be NULL.
+   * \param[in]    num_enc Total number of encoders.
+   * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
+   * \param[in]    dsf     Pointer to down-sampling factors.
+   * \param[in]    ver     ABI version number. Must be set to
+   *                       VPX_ENCODER_ABI_VERSION
+   * \retval #VPX_CODEC_OK
+   *     The decoder algorithm initialized.
+   * \retval #VPX_CODEC_MEM_ERROR
+   *     Memory allocation failed.
+   */
+  vpx_codec_err_t vpx_codec_enc_init_multi_ver(vpx_codec_ctx_t      *ctx,
+                                               vpx_codec_iface_t    *iface,
+                                               vpx_codec_enc_cfg_t  *cfg,
+                                               int                   num_enc,
+                                               vpx_codec_flags_t     flags,
+                                               vpx_rational_t       *dsf,
+                                               int                   ver);
+
+
+  /*!\brief Convenience macro for vpx_codec_enc_init_multi_ver()
+   *
+   * Ensures the ABI version parameter is properly set.
+   */
 #define vpx_codec_enc_init_multi(ctx, iface, cfg, num_enc, flags, dsf) \
-    vpx_codec_enc_init_multi_ver(ctx, iface, cfg, num_enc, flags, dsf, \
-                                 VPX_ENCODER_ABI_VERSION)
-
-
-    /*!\brief Get a default configuration
-     *
-     * Initializes a encoder configuration structure with default values. Supports
-     * the notion of "usages" so that an algorithm may offer different default
-     * settings depending on the user's intended goal. This function \ref SHOULD
-     * be called by all applications to initialize the configuration structure
-     * before specializing the configuration with application specific values.
-     *
-     * \param[in]    iface   Pointer to the algorithm interface to use.
-     * \param[out]   cfg     Configuration buffer to populate
-     * \param[in]    usage   End usage. Set to 0 or use codec specific values.
-     *
-     * \retval #VPX_CODEC_OK
-     *     The configuration was populated.
-     * \retval #VPX_CODEC_INCAPABLE
-     *     Interface is not an encoder interface.
-     * \retval #VPX_CODEC_INVALID_PARAM
-     *     A parameter was NULL, or the usage value was not recognized.
-     */
-    vpx_codec_err_t  vpx_codec_enc_config_default(vpx_codec_iface_t    *iface,
-            vpx_codec_enc_cfg_t  *cfg,
-            unsigned int          usage);
-
-
-    /*!\brief Set or change configuration
-     *
-     * Reconfigures an encoder instance according to the given configuration.
-     *
-     * \param[in]    ctx     Pointer to this instance's context
-     * \param[in]    cfg     Configuration buffer to use
-     *
-     * \retval #VPX_CODEC_OK
-     *     The configuration was populated.
-     * \retval #VPX_CODEC_INCAPABLE
-     *     Interface is not an encoder interface.
-     * \retval #VPX_CODEC_INVALID_PARAM
-     *     A parameter was NULL, or the usage value was not recognized.
-     */
-    vpx_codec_err_t  vpx_codec_enc_config_set(vpx_codec_ctx_t            *ctx,
-            const vpx_codec_enc_cfg_t  *cfg);
-
-
-    /*!\brief Get global stream headers
-     *
-     * Retrieves a stream level global header packet, if supported by the codec.
-     *
-     * \param[in]    ctx     Pointer to this instance's context
-     *
-     * \retval NULL
-     *     Encoder does not support global header
-     * \retval Non-NULL
-     *     Pointer to buffer containing global header packet
-     */
-    vpx_fixed_buf_t *vpx_codec_get_global_headers(vpx_codec_ctx_t   *ctx);
+  vpx_codec_enc_init_multi_ver(ctx, iface, cfg, num_enc, flags, dsf, \
+                               VPX_ENCODER_ABI_VERSION)
+
+
+  /*!\brief Get a default configuration
+   *
+   * Initializes a encoder configuration structure with default values. Supports
+   * the notion of "usages" so that an algorithm may offer different default
+   * settings depending on the user's intended goal. This function \ref SHOULD
+   * be called by all applications to initialize the configuration structure
+   * before specializing the configuration with application specific values.
+   *
+   * \param[in]    iface   Pointer to the algorithm interface to use.
+   * \param[out]   cfg     Configuration buffer to populate
+   * \param[in]    usage   End usage. Set to 0 or use codec specific values.
+   *
+   * \retval #VPX_CODEC_OK
+   *     The configuration was populated.
+   * \retval #VPX_CODEC_INCAPABLE
+   *     Interface is not an encoder interface.
+   * \retval #VPX_CODEC_INVALID_PARAM
+   *     A parameter was NULL, or the usage value was not recognized.
+   */
+  vpx_codec_err_t  vpx_codec_enc_config_default(vpx_codec_iface_t    *iface,
+                                                vpx_codec_enc_cfg_t  *cfg,
+                                                unsigned int          usage);
+
+
+  /*!\brief Set or change configuration
+   *
+   * Reconfigures an encoder instance according to the given configuration.
+   *
+   * \param[in]    ctx     Pointer to this instance's context
+   * \param[in]    cfg     Configuration buffer to use
+   *
+   * \retval #VPX_CODEC_OK
+   *     The configuration was populated.
+   * \retval #VPX_CODEC_INCAPABLE
+   *     Interface is not an encoder interface.
+   * \retval #VPX_CODEC_INVALID_PARAM
+   *     A parameter was NULL, or the usage value was not recognized.
+   */
+  vpx_codec_err_t  vpx_codec_enc_config_set(vpx_codec_ctx_t            *ctx,
+                                            const vpx_codec_enc_cfg_t  *cfg);
+
+
+  /*!\brief Get global stream headers
+   *
+   * Retrieves a stream level global header packet, if supported by the codec.
+   *
+   * \param[in]    ctx     Pointer to this instance's context
+   *
+   * \retval NULL
+   *     Encoder does not support global header
+   * \retval Non-NULL
+   *     Pointer to buffer containing global header packet
+   */
+  vpx_fixed_buf_t *vpx_codec_get_global_headers(vpx_codec_ctx_t   *ctx);
 
 
 #define VPX_DL_REALTIME     (1)        /**< deadline parameter analogous to
-    *   VPx REALTIME mode. */
+  *   VPx REALTIME mode. */
 #define VPX_DL_GOOD_QUALITY (1000000)  /**< deadline parameter analogous to
-    *   VPx GOOD QUALITY mode. */
+  *   VPx GOOD QUALITY mode. */
 #define VPX_DL_BEST_QUALITY (0)        /**< deadline parameter analogous to
-    *   VPx BEST QUALITY mode. */
-    /*!\brief Encode a frame
-     *
-     * Encodes a video frame at the given "presentation time." The presentation
-     * time stamp (PTS) \ref MUST be strictly increasing.
-     *
-     * The encoder supports the notion of a soft real-time deadline. Given a
-     * non-zero value to the deadline parameter, the encoder will make a "best
-     * effort" guarantee to  return before the given time slice expires. It is
-     * implicit that limiting the available time to encode will degrade the
-     * output quality. The encoder can be given an unlimited time to produce the
-     * best possible frame by specifying a deadline of '0'. This deadline
-     * supercedes the VPx notion of "best quality, good quality, realtime".
-     * Applications that wish to map these former settings to the new deadline
-     * based system can use the symbols #VPX_DL_REALTIME, #VPX_DL_GOOD_QUALITY,
-     * and #VPX_DL_BEST_QUALITY.
-     *
-     * When the last frame has been passed to the encoder, this function should
-     * continue to be called, with the img parameter set to NULL. This will
-     * signal the end-of-stream condition to the encoder and allow it to encode
-     * any held buffers. Encoding is complete when vpx_codec_encode() is called
-     * and vpx_codec_get_cx_data() returns no data.
-     *
-     * \param[in]    ctx       Pointer to this instance's context
-     * \param[in]    img       Image data to encode, NULL to flush.
-     * \param[in]    pts       Presentation time stamp, in timebase units.
-     * \param[in]    duration  Duration to show frame, in timebase units.
-     * \param[in]    flags     Flags to use for encoding this frame.
-     * \param[in]    deadline  Time to spend encoding, in microseconds. (0=infinite)
-     *
-     * \retval #VPX_CODEC_OK
-     *     The configuration was populated.
-     * \retval #VPX_CODEC_INCAPABLE
-     *     Interface is not an encoder interface.
-     * \retval #VPX_CODEC_INVALID_PARAM
-     *     A parameter was NULL, the image format is unsupported, etc.
-     */
-    vpx_codec_err_t  vpx_codec_encode(vpx_codec_ctx_t            *ctx,
-                                      const vpx_image_t          *img,
-                                      vpx_codec_pts_t             pts,
-                                      unsigned long               duration,
-                                      vpx_enc_frame_flags_t       flags,
-                                      unsigned long               deadline);
-
-    /*!\brief Set compressed data output buffer
-     *
-     * Sets the buffer that the codec should output the compressed data
-     * into. This call effectively sets the buffer pointer returned in the
-     * next VPX_CODEC_CX_FRAME_PKT packet. Subsequent packets will be
-     * appended into this buffer. The buffer is preserved across frames,
-     * so applications must periodically call this function after flushing
-     * the accumulated compressed data to disk or to the network to reset
-     * the pointer to the buffer's head.
-     *
-     * `pad_before` bytes will be skipped before writing the compressed
-     * data, and `pad_after` bytes will be appended to the packet. The size
-     * of the packet will be the sum of the size of the actual compressed
-     * data, pad_before, and pad_after. The padding bytes will be preserved
-     * (not overwritten).
-     *
-     * Note that calling this function does not guarantee that the returned
-     * compressed data will be placed into the specified buffer. In the
-     * event that the encoded data will not fit into the buffer provided,
-     * the returned packet \ref MAY point to an internal buffer, as it would
-     * if this call were never used. In this event, the output packet will
-     * NOT have any padding, and the application must free space and copy it
-     * to the proper place. This is of particular note in configurations
-     * that may output multiple packets for a single encoded frame (e.g., lagged
-     * encoding) or if the application does not reset the buffer periodically.
-     *
-     * Applications may restore the default behavior of the codec providing
-     * the compressed data buffer by calling this function with a NULL
-     * buffer.
-     *
-     * Applications \ref MUSTNOT call this function during iteration of
-     * vpx_codec_get_cx_data().
-     *
-     * \param[in]    ctx         Pointer to this instance's context
-     * \param[in]    buf         Buffer to store compressed data into
-     * \param[in]    pad_before  Bytes to skip before writing compressed data
-     * \param[in]    pad_after   Bytes to skip after writing compressed data
-     *
-     * \retval #VPX_CODEC_OK
-     *     The buffer was set successfully.
-     * \retval #VPX_CODEC_INVALID_PARAM
-     *     A parameter was NULL, the image format is unsupported, etc.
-     */
-    vpx_codec_err_t vpx_codec_set_cx_data_buf(vpx_codec_ctx_t       *ctx,
-            const vpx_fixed_buf_t *buf,
-            unsigned int           pad_before,
-            unsigned int           pad_after);
-
-
-    /*!\brief Encoded data iterator
-     *
-     * Iterates over a list of data packets to be passed from the encoder to the
-     * application. The different kinds of packets available are enumerated in
-     * #vpx_codec_cx_pkt_kind.
-     *
-     * #VPX_CODEC_CX_FRAME_PKT packets should be passed to the application's
-     * muxer. Multiple compressed frames may be in the list.
-     * #VPX_CODEC_STATS_PKT packets should be appended to a global buffer.
-     *
-     * The application \ref MUST silently ignore any packet kinds that it does
-     * not recognize or support.
-     *
-     * The data buffers returned from this function are only guaranteed to be
-     * valid until the application makes another call to any vpx_codec_* function.
-     *
-     * \param[in]     ctx      Pointer to this instance's context
-     * \param[in,out] iter     Iterator storage, initialized to NULL
-     *
-     * \return Returns a pointer to an output data packet (compressed frame data,
-     *         two-pass statistics, etc.) or NULL to signal end-of-list.
-     *
-     */
-    const vpx_codec_cx_pkt_t *vpx_codec_get_cx_data(vpx_codec_ctx_t   *ctx,
-            vpx_codec_iter_t  *iter);
-
-
-    /*!\brief Get Preview Frame
-     *
-     * Returns an image that can be used as a preview. Shows the image as it would
-     * exist at the decompressor. The application \ref MUST NOT write into this
-     * image buffer.
-     *
-     * \param[in]     ctx      Pointer to this instance's context
-     *
-     * \return Returns a pointer to a preview image, or NULL if no image is
-     *         available.
-     *
-     */
-    const vpx_image_t *vpx_codec_get_preview_frame(vpx_codec_ctx_t   *ctx);
-
-
-    /*!@} - end defgroup encoder*/
+  *   VPx BEST QUALITY mode. */
+  /*!\brief Encode a frame
+   *
+   * Encodes a video frame at the given "presentation time." The presentation
+   * time stamp (PTS) \ref MUST be strictly increasing.
+   *
+   * The encoder supports the notion of a soft real-time deadline. Given a
+   * non-zero value to the deadline parameter, the encoder will make a "best
+   * effort" guarantee to  return before the given time slice expires. It is
+   * implicit that limiting the available time to encode will degrade the
+   * output quality. The encoder can be given an unlimited time to produce the
+   * best possible frame by specifying a deadline of '0'. This deadline
+   * supercedes the VPx notion of "best quality, good quality, realtime".
+   * Applications that wish to map these former settings to the new deadline
+   * based system can use the symbols #VPX_DL_REALTIME, #VPX_DL_GOOD_QUALITY,
+   * and #VPX_DL_BEST_QUALITY.
+   *
+   * When the last frame has been passed to the encoder, this function should
+   * continue to be called, with the img parameter set to NULL. This will
+   * signal the end-of-stream condition to the encoder and allow it to encode
+   * any held buffers. Encoding is complete when vpx_codec_encode() is called
+   * and vpx_codec_get_cx_data() returns no data.
+   *
+   * \param[in]    ctx       Pointer to this instance's context
+   * \param[in]    img       Image data to encode, NULL to flush.
+   * \param[in]    pts       Presentation time stamp, in timebase units.
+   * \param[in]    duration  Duration to show frame, in timebase units.
+   * \param[in]    flags     Flags to use for encoding this frame.
+   * \param[in]    deadline  Time to spend encoding, in microseconds. (0=infinite)
+   *
+   * \retval #VPX_CODEC_OK
+   *     The configuration was populated.
+   * \retval #VPX_CODEC_INCAPABLE
+   *     Interface is not an encoder interface.
+   * \retval #VPX_CODEC_INVALID_PARAM
+   *     A parameter was NULL, the image format is unsupported, etc.
+   */
+  vpx_codec_err_t  vpx_codec_encode(vpx_codec_ctx_t            *ctx,
+                                    const vpx_image_t          *img,
+                                    vpx_codec_pts_t             pts,
+                                    unsigned long               duration,
+                                    vpx_enc_frame_flags_t       flags,
+                                    unsigned long               deadline);
+
+  /*!\brief Set compressed data output buffer
+   *
+   * Sets the buffer that the codec should output the compressed data
+   * into. This call effectively sets the buffer pointer returned in the
+   * next VPX_CODEC_CX_FRAME_PKT packet. Subsequent packets will be
+   * appended into this buffer. The buffer is preserved across frames,
+   * so applications must periodically call this function after flushing
+   * the accumulated compressed data to disk or to the network to reset
+   * the pointer to the buffer's head.
+   *
+   * `pad_before` bytes will be skipped before writing the compressed
+   * data, and `pad_after` bytes will be appended to the packet. The size
+   * of the packet will be the sum of the size of the actual compressed
+   * data, pad_before, and pad_after. The padding bytes will be preserved
+   * (not overwritten).
+   *
+   * Note that calling this function does not guarantee that the returned
+   * compressed data will be placed into the specified buffer. In the
+   * event that the encoded data will not fit into the buffer provided,
+   * the returned packet \ref MAY point to an internal buffer, as it would
+   * if this call were never used. In this event, the output packet will
+   * NOT have any padding, and the application must free space and copy it
+   * to the proper place. This is of particular note in configurations
+   * that may output multiple packets for a single encoded frame (e.g., lagged
+   * encoding) or if the application does not reset the buffer periodically.
+   *
+   * Applications may restore the default behavior of the codec providing
+   * the compressed data buffer by calling this function with a NULL
+   * buffer.
+   *
+   * Applications \ref MUSTNOT call this function during iteration of
+   * vpx_codec_get_cx_data().
+   *
+   * \param[in]    ctx         Pointer to this instance's context
+   * \param[in]    buf         Buffer to store compressed data into
+   * \param[in]    pad_before  Bytes to skip before writing compressed data
+   * \param[in]    pad_after   Bytes to skip after writing compressed data
+   *
+   * \retval #VPX_CODEC_OK
+   *     The buffer was set successfully.
+   * \retval #VPX_CODEC_INVALID_PARAM
+   *     A parameter was NULL, the image format is unsupported, etc.
+   */
+  vpx_codec_err_t vpx_codec_set_cx_data_buf(vpx_codec_ctx_t       *ctx,
+                                            const vpx_fixed_buf_t *buf,
+                                            unsigned int           pad_before,
+                                            unsigned int           pad_after);
+
+
+  /*!\brief Encoded data iterator
+   *
+   * Iterates over a list of data packets to be passed from the encoder to the
+   * application. The different kinds of packets available are enumerated in
+   * #vpx_codec_cx_pkt_kind.
+   *
+   * #VPX_CODEC_CX_FRAME_PKT packets should be passed to the application's
+   * muxer. Multiple compressed frames may be in the list.
+   * #VPX_CODEC_STATS_PKT packets should be appended to a global buffer.
+   *
+   * The application \ref MUST silently ignore any packet kinds that it does
+   * not recognize or support.
+   *
+   * The data buffers returned from this function are only guaranteed to be
+   * valid until the application makes another call to any vpx_codec_* function.
+   *
+   * \param[in]     ctx      Pointer to this instance's context
+   * \param[in,out] iter     Iterator storage, initialized to NULL
+   *
+   * \return Returns a pointer to an output data packet (compressed frame data,
+   *         two-pass statistics, etc.) or NULL to signal end-of-list.
+   *
+   */
+  const vpx_codec_cx_pkt_t *vpx_codec_get_cx_data(vpx_codec_ctx_t   *ctx,
+                                                  vpx_codec_iter_t  *iter);
+
+
+  /*!\brief Get Preview Frame
+   *
+   * Returns an image that can be used as a preview. Shows the image as it would
+   * exist at the decompressor. The application \ref MUST NOT write into this
+   * image buffer.
+   *
+   * \param[in]     ctx      Pointer to this instance's context
+   *
+   * \return Returns a pointer to a preview image, or NULL if no image is
+   *         available.
+   *
+   */
+  const vpx_image_t *vpx_codec_get_preview_frame(vpx_codec_ctx_t   *ctx);
+
+
+  /*!@} - end defgroup encoder*/
 
 #endif
 #ifdef __cplusplus
 }
 #endif