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.
12 // VP8 Set Reference Frame
13 // =======================
15 // This is an example demonstrating how to overwrite the VP8 encoder's
16 // internal reference frame. In the sample we set the last frame to the
17 // current frame. If this is done at a cut scene it will avoid a keyframe.
18 // This technique could be used to bounce between two cameras.
20 // Note that the decoder would also have to set the reference frame to the
21 // same value on the same frame, or the video will become corrupt.
25 // This example adds a single argument to the `simple_encoder` example,
26 // which specifies the frame number to update the reference frame on.
27 // The parameter is parsed as follows:
32 // This example maintains the frame number passed on the command line
33 // in the `update_frame_num` variable.
39 // The reference frame is updated on the frame specified on the command
42 // Observing The Effects
43 // ---------------------
44 // Use the `simple_encoder` example to encode a sample with a cut scene.
45 // Determine the frame number of the cut scene by looking for a generated
46 // key-frame (indicated by a 'K'). Supply that frame number as an argument
47 // to this example, and observe that no key-frame is generated.
53 #define VPX_CODEC_DISABLE_COMPAT 1
54 #include "vpx/vp8cx.h"
55 #include "vpx/vpx_encoder.h"
57 #include "./tools_common.h"
58 #include "./video_writer.h"
60 static const char *exec_name;
63 fprintf(stderr, "Usage: %s <width> <height> <infile> <outfile> <frame>\n",
68 static int encode_frame(vpx_codec_ctx_t *codec,
71 VpxVideoWriter *writer) {
73 vpx_codec_iter_t iter = NULL;
74 const vpx_codec_cx_pkt_t *pkt = NULL;
75 const vpx_codec_err_t res = vpx_codec_encode(codec, img, frame_index, 1, 0,
77 if (res != VPX_CODEC_OK)
78 die_codec(codec, "Failed to encode frame");
80 while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) {
83 if (pkt->kind == VPX_CODEC_CX_FRAME_PKT) {
84 const int keyframe = (pkt->data.frame.flags & VPX_FRAME_IS_KEY) != 0;
85 if (!vpx_video_writer_write_frame(writer,
88 pkt->data.frame.pts)) {
89 die_codec(codec, "Failed to write compressed frame");
92 printf(keyframe ? "K" : ".");
100 int main(int argc, char **argv) {
102 vpx_codec_ctx_t codec = {0};
103 vpx_codec_enc_cfg_t cfg = {0};
107 VpxVideoInfo info = {0};
108 VpxVideoWriter *writer = NULL;
109 const VpxInterface *encoder = NULL;
110 int update_frame_num = 0;
111 const int fps = 30; // TODO(dkovalev) add command line argument
112 const int bitrate = 200; // kbit/s TODO(dkovalev) add command line argument
117 die("Invalid number of arguments");
119 // TODO(dkovalev): add vp9 support and rename the file accordingly
120 encoder = get_vpx_encoder_by_name("vp8");
122 die("Unsupported codec.");
124 update_frame_num = atoi(argv[5]);
125 if (!update_frame_num)
126 die("Couldn't parse frame number '%s'\n", argv[5]);
128 info.codec_fourcc = encoder->fourcc;
129 info.frame_width = strtol(argv[1], NULL, 0);
130 info.frame_height = strtol(argv[2], NULL, 0);
131 info.time_base.numerator = 1;
132 info.time_base.denominator = fps;
134 if (info.frame_width <= 0 ||
135 info.frame_height <= 0 ||
136 (info.frame_width % 2) != 0 ||
137 (info.frame_height % 2) != 0) {
138 die("Invalid frame size: %dx%d", info.frame_width, info.frame_height);
141 if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, info.frame_width,
142 info.frame_height, 1)) {
143 die("Failed to allocate image.");
146 printf("Using %s\n", vpx_codec_iface_name(encoder->codec_interface()));
148 res = vpx_codec_enc_config_default(encoder->codec_interface(), &cfg, 0);
150 die_codec(&codec, "Failed to get default codec config.");
152 cfg.g_w = info.frame_width;
153 cfg.g_h = info.frame_height;
154 cfg.g_timebase.num = info.time_base.numerator;
155 cfg.g_timebase.den = info.time_base.denominator;
156 cfg.rc_target_bitrate = bitrate;
158 writer = vpx_video_writer_open(argv[4], kContainerIVF, &info);
160 die("Failed to open %s for writing.", argv[4]);
162 if (!(infile = fopen(argv[3], "rb")))
163 die("Failed to open %s for reading.", argv[3]);
165 if (vpx_codec_enc_init(&codec, encoder->codec_interface(), &cfg, 0))
166 die_codec(&codec, "Failed to initialize encoder");
169 while (vpx_img_read(&raw, infile)) {
170 if (frame_count + 1 == update_frame_num) {
172 ref.frame_type = VP8_LAST_FRAME;
174 if (vpx_codec_control(&codec, VP8_SET_REFERENCE, &ref))
175 die_codec(&codec, "Failed to set reference frame");
178 encode_frame(&codec, &raw, frame_count++, writer);
182 while (encode_frame(&codec, NULL, -1, writer)) {};
186 printf("Processed %d frames.\n", frame_count);
189 if (vpx_codec_destroy(&codec))
190 die_codec(&codec, "Failed to destroy codec.");
192 vpx_video_writer_close(writer);