2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
11 // Decode With Drops Example
12 // =========================
14 // This is an example utility which drops a series of frames, as specified
15 // on the command line. This is useful for observing the error recovery
16 // features of the codec.
20 // This example adds a single argument to the `simple_decoder` example,
21 // which specifies the range or pattern of frames to drop. The parameter is
24 // Dropping A Range Of Frames
25 // --------------------------
26 // To drop a range of frames, specify the starting frame and the ending
27 // frame to drop, separated by a dash. The following command will drop
28 // frames 5 through 10 (base 1).
30 // $ ./decode_with_drops in.ivf out.i420 5-10
33 // Dropping A Pattern Of Frames
34 // ----------------------------
35 // To drop a pattern of frames, specify the number of frames to drop and
36 // the number of frames after which to repeat the pattern, separated by
37 // a forward-slash. The following command will drop 3 of 7 frames.
38 // Specifically, it will decode 4 frames, then drop 3 frames, and then
41 // $ ./decode_with_drops in.ivf out.i420 3/7
46 // This example maintains the pattern passed on the command line in the
47 // `n`, `m`, and `is_range` variables:
50 // Making The Drop Decision
51 // ------------------------
52 // The example decides whether to drop the frame based on the current
53 // frame number, immediately before decoding the frame.
59 #define VPX_CODEC_DISABLE_COMPAT 1
61 #include "vpx/vp8dx.h"
62 #include "vpx/vpx_decoder.h"
64 #include "./tools_common.h"
65 #include "./video_reader.h"
66 #include "./vpx_config.h"
68 static const char *exec_name;
71 fprintf(stderr, "Usage: %s <infile> <outfile> <N-M|N/M>\n", exec_name);
75 int main(int argc, char **argv) {
78 vpx_codec_ctx_t codec;
79 const VpxInterface *decoder = NULL;
80 VpxVideoReader *reader = NULL;
81 const VpxVideoInfo *info = NULL;
90 die("Invalid number of arguments.");
92 reader = vpx_video_reader_open(argv[1]);
94 die("Failed to open %s for reading.", argv[1]);
96 if (!(outfile = fopen(argv[2], "wb")))
97 die("Failed to open %s for writing.", argv[2]);
99 n = strtol(argv[3], &nptr, 0);
100 m = strtol(nptr + 1, NULL, 0);
101 is_range = (*nptr == '-');
102 if (!n || !m || (*nptr != '-' && *nptr != '/'))
103 die("Couldn't parse pattern %s.\n", argv[3]);
105 info = vpx_video_reader_get_info(reader);
107 decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
109 die("Unknown input codec.");
111 printf("Using %s\n", vpx_codec_iface_name(decoder->interface()));
113 if (vpx_codec_dec_init(&codec, decoder->interface(), NULL, 0))
114 die_codec(&codec, "Failed to initialize decoder.");
116 while (vpx_video_reader_read_frame(reader)) {
117 vpx_codec_iter_t iter = NULL;
118 vpx_image_t *img = NULL;
119 size_t frame_size = 0;
121 const unsigned char *frame = vpx_video_reader_get_frame(reader,
123 if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
124 die_codec(&codec, "Failed to decode frame.");
128 skip = (is_range && frame_cnt >= n && frame_cnt <= m) ||
129 (!is_range && m - (frame_cnt - 1) % m <= n);
134 while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL)
135 vpx_img_write(img, outfile);
143 printf("Processed %d frames.\n", frame_cnt);
144 if (vpx_codec_destroy(&codec))
145 die_codec(&codec, "Failed to destroy codec.");
147 printf("Play: ffplay -f rawvideo -pix_fmt yuv420p -s %dx%d %s\n",
148 info->frame_width, info->frame_height, argv[2]);
150 vpx_video_reader_close(reader);