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| 1 // Copyright 2014 The Chromium Authors. All rights reserved. |
| 2 // Use of this source code is governed by a BSD-style license that can be |
| 3 // found in the LICENSE file. |
| 4 |
| 5 #ifndef MEDIA_FORMATS_WEBM_CHROMEOS_WEBM_ENCODER_H_ |
| 6 #define MEDIA_FORMATS_WEBM_CHROMEOS_WEBM_ENCODER_H_ |
| 7 |
| 8 #include <stdio.h> |
| 9 #include <stack> |
| 10 |
| 11 #include "base/files/file_path.h" |
| 12 #include "media/base/media_export.h" |
| 13 #include "media/formats/webm/chromeos/ebml_writer.h" |
| 14 |
| 15 extern "C" { |
| 16 #define VPX_CODEC_DISABLE_COMPAT 1 |
| 17 #include "third_party/libvpx/source/libvpx/vpx/vpx_encoder.h" |
| 18 #include "third_party/libvpx/source/libvpx/vpx/vp8cx.h" |
| 19 } |
| 20 |
| 21 class SkBitmap; |
| 22 |
| 23 namespace base { |
| 24 class FilePath; |
| 25 } |
| 26 |
| 27 namespace media { |
| 28 |
| 29 namespace chromeos { |
| 30 |
| 31 // WebM encoder using libvpx. Currently only supports one-pass, constant bitrate |
| 32 // encoding of short files consisting of a single video track. Seek info and |
| 33 // cues are not supported, so generated .webm file does not strictly adhere to |
| 34 // WebM standard (http://www.webmproject.org/code/specs/container/). |
| 35 class MEDIA_EXPORT WebmEncoder { |
| 36 public: |
| 37 // Create new instance for writing to |output_path|. If |realtime| is |true|, |
| 38 // uses realtime deadline, otherwise - "good quality" deadline. |
| 39 WebmEncoder(const base::FilePath& output_path, int bitrate, bool realtime); |
| 40 ~WebmEncoder(); |
| 41 |
| 42 // Encodes video from a Nx(N*M) sprite, having M frames of size NxN with FPS |
| 43 // |fps_n/fps_d|. Must be called on a thread that allows disk IO. |
| 44 // Returns |true| iff encoding and writing to file is successful. |
| 45 bool EncodeFromSprite(const SkBitmap& sprite, int fps_n, int fps_d); |
| 46 |
| 47 private: |
| 48 // Writes global WebM header and starts a single video track. Returns |false| |
| 49 // if there was an error opening file for writing. |
| 50 bool WriteWebmHeader(); |
| 51 |
| 52 // Writes VPX packet to output file. |
| 53 void WriteWebmBlock(const vpx_codec_cx_pkt_t* packet); |
| 54 |
| 55 // Finishes video track and closes output file. Returns |false| if there were |
| 56 // any error during encoding/writing file. |
| 57 bool WriteWebmFooter(); |
| 58 |
| 59 // Starts a new WebM sub-element of given type. Those can be nested. |
| 60 void StartSubElement(unsigned long class_id); |
| 61 |
| 62 // Closes current top-level sub-element. |
| 63 void EndSubElement(); |
| 64 |
| 65 // libmkv callbacks. |
| 66 void EbmlWrite(const void* buffer, unsigned long len); |
| 67 void EbmlSerialize(const void* buffer, int buffer_size, unsigned long len); |
| 68 |
| 69 template <typename T> |
| 70 void EbmlSerializeHelper(const T* buffer, unsigned long len); |
| 71 |
| 72 // Video dimensions and FPS. |
| 73 size_t width_; |
| 74 size_t height_; |
| 75 vpx_rational_t fps_; |
| 76 |
| 77 // Number of frames in video. |
| 78 size_t frame_count_; |
| 79 |
| 80 // VPX config in use. |
| 81 vpx_codec_enc_cfg_t config_; |
| 82 |
| 83 // VPX parameters. |
| 84 int bitrate_; |
| 85 unsigned long deadline_; |
| 86 |
| 87 // EbmlWriter context. |
| 88 EbmlGlobal ebml_writer_; |
| 89 |
| 90 // Stack with start offsets of currently open sub-elements. |
| 91 std::stack<long int> ebml_sub_elements_; |
| 92 |
| 93 base::FilePath output_path_; |
| 94 FILE* output_; |
| 95 |
| 96 // True if an error occured while encoding/writing to file. |
| 97 bool has_errors_; |
| 98 |
| 99 DISALLOW_COPY_AND_ASSIGN(WebmEncoder); |
| 100 }; |
| 101 |
| 102 } // namespace chromeos |
| 103 |
| 104 } // namespace media |
| 105 |
| 106 #endif // MEDIA_FORMATS_WEBM_CHROMEOS_WEBM_ENCODER_H_ |
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