libvpx: Pull from upstream

source/libvpx/examples/decode_with_drops.c

Index: source/libvpx/examples/decode_with_drops.c
===================================================================
--- source/libvpx/examples/decode_with_drops.c	(revision 0)
+++ source/libvpx/examples/decode_with_drops.c	(revision 0)
@@ -0,0 +1,177 @@
+/*
+ *  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.
+ */
+
+// Decode With Drops Example
+// =========================
+//
+// This is an example utility which drops a series of frames, as specified
+// on the command line. This is useful for observing the error recovery
+// features of the codec.
+//
+// Usage
+// -----
+// This example adds a single argument to the `simple_decoder` example,
+// which specifies the range or pattern of frames to drop. The parameter is
+// parsed as follows:
+//
+// Dropping A Range Of Frames
+// --------------------------
+// To drop a range of frames, specify the starting frame and the ending
+// frame to drop, separated by a dash. The following command will drop
+// frames 5 through 10 (base 1).
+//
+//  $ ./decode_with_drops in.ivf out.i420 5-10
+//
+//
+// Dropping A Pattern Of Frames
+// ----------------------------
+// To drop a pattern of frames, specify the number of frames to drop and
+// the number of frames after which to repeat the pattern, separated by
+// a forward-slash. The following command will drop 3 of 7 frames.
+// Specifically, it will decode 4 frames, then drop 3 frames, and then
+// repeat.
+//
+//  $ ./decode_with_drops in.ivf out.i420 3/7
+//
+//
+// Extra Variables
+// ---------------
+// This example maintains the pattern passed on the command line in the
+// `n`, `m`, and `is_range` variables:
+//
+//
+// Making The Drop Decision
+// ------------------------
+// The example decides whether to drop the frame based on the current
+// frame number, immediately before decoding the frame.
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#define VPX_CODEC_DISABLE_COMPAT 1
+#include "./vpx_config.h"
+#include "vpx/vp8dx.h"
+#include "vpx/vpx_decoder.h"
+#define interface (vpx_codec_vp8_dx())
+
+
+#define IVF_FILE_HDR_SZ  (32)
+#define IVF_FRAME_HDR_SZ (12)
+
+static unsigned int mem_get_le32(const unsigned char *mem) {
+    return (mem[3] << 24)|(mem[2] << 16)|(mem[1] << 8)|(mem[0]);
+}
+
+static void die(const char *fmt, ...) {
+    va_list ap;
+
+    va_start(ap, fmt);
+    vprintf(fmt, ap);
+    if(fmt[strlen(fmt)-1] != '\n')
+        printf("\n");
+    exit(EXIT_FAILURE);
+}
+
+static void die_codec(vpx_codec_ctx_t *ctx, const char *s) {
+    const char *detail = vpx_codec_error_detail(ctx);
+
+    printf("%s: %s\n", s, vpx_codec_error(ctx));
+    if(detail)
+        printf("    %s\n",detail);
+    exit(EXIT_FAILURE);
+}
+
+
+int main(int argc, char **argv) {
+    FILE            *infile, *outfile;
+    vpx_codec_ctx_t  codec;
+    int              flags = 0, frame_cnt = 0;
+    unsigned char    file_hdr[IVF_FILE_HDR_SZ];
+    unsigned char    frame_hdr[IVF_FRAME_HDR_SZ];
+    unsigned char    frame[256*1024];
+    vpx_codec_err_t  res;
+    int              n, m, is_range;
+
+    (void)res;
+    /* Open files */
+    if(argc!=4)
+        die("Usage: %s <infile> <outfile> <N-M|N/M>\n", argv[0]);
+    {
+        char *nptr;
+        n = strtol(argv[3], &nptr, 0);
+        m = strtol(nptr+1, NULL, 0);
+        is_range = *nptr == '-';
+        if(!n || !m || (*nptr != '-' && *nptr != '/'))
+            die("Couldn't parse pattern %s\n", argv[3]);
+    }
+    if(!(infile = fopen(argv[1], "rb")))
+        die("Failed to open %s for reading", argv[1]);
+    if(!(outfile = fopen(argv[2], "wb")))
+        die("Failed to open %s for writing", argv[2]);
+
+    /* Read file header */
+    if(!(fread(file_hdr, 1, IVF_FILE_HDR_SZ, infile) == IVF_FILE_HDR_SZ
+         && file_hdr[0]=='D' && file_hdr[1]=='K' && file_hdr[2]=='I'
+         && file_hdr[3]=='F'))
+        die("%s is not an IVF file.", argv[1]);
+
+    printf("Using %s\n",vpx_codec_iface_name(interface));
+    /* Initialize codec */
+    if(vpx_codec_dec_init(&codec, interface, NULL, flags))
+        die_codec(&codec, "Failed to initialize decoder");
+
+    /* Read each frame */
+    while(fread(frame_hdr, 1, IVF_FRAME_HDR_SZ, infile) == IVF_FRAME_HDR_SZ) {
+        int               frame_sz = mem_get_le32(frame_hdr);
+        vpx_codec_iter_t  iter = NULL;
+        vpx_image_t      *img;
+
+
+        frame_cnt++;
+        if(frame_sz > sizeof(frame))
+            die("Frame %d data too big for example code buffer", frame_sz);
+        if(fread(frame, 1, frame_sz, infile) != frame_sz)
+            die("Frame %d failed to read complete frame", frame_cnt);
+
+        if((is_range && frame_cnt >= n && frame_cnt <= m)
+           ||(!is_range && m - (frame_cnt-1)%m <= n)) {
+           putc('X', stdout);
+           continue;
+        }
+        putc('.', stdout);
+        fflush(stdout);
+        /* Decode the frame */
+        if(vpx_codec_decode(&codec, frame, frame_sz, NULL, 0))
+            die_codec(&codec, "Failed to decode frame");
+
+        /* Write decoded data to disk */
+        while((img = vpx_codec_get_frame(&codec, &iter))) {
+            unsigned int plane, y;
+
+            for(plane=0; plane < 3; plane++) {
+                unsigned char *buf =img->planes[plane];
+            
+                for(y=0; y < (plane ? (img->d_h + 1) >> 1 : img->d_h); y++) {
+                    (void) fwrite(buf, 1, (plane ? (img->d_w + 1) >> 1 : img->d_w),
+                                  outfile);
+                    buf += img->stride[plane];
+                }
+            }
+        }
+    }
+    printf("Processed %d frames.\n",frame_cnt);
+    if(vpx_codec_destroy(&codec))
+        die_codec(&codec, "Failed to destroy codec");
+
+    fclose(outfile);
+    fclose(infile);
+    return EXIT_SUCCESS;
+}