examples/vp8cx_set_ref.c

   1 /*
   2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   3  *
   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.
   9  */
  10
  11
  12 // VP8 Set Reference Frame
  13 // =======================
  14 //
  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.
  19 //
  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.
  22 //
  23 // Usage
  24 // -----
  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:
  28 //
  29 //
  30 // Extra Variables
  31 // ---------------
  32 // This example maintains the frame number passed on the command line
  33 // in the `update_frame_num` variable.
  34 //
  35 //
  36 // Configuration
  37 // -------------
  38 //
  39 // The reference frame is updated on the frame specified on the command
  40 // line.
  41 //
  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.
  48
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52
  53 #include "vpx/vp8cx.h"
  54 #include "vpx/vpx_encoder.h"
  55
  56 #include "../tools_common.h"
  57 #include "../video_writer.h"
  58
  59 static const char *exec_name;
  60
  61 void usage_exit(void) {
  62   fprintf(stderr, "Usage: %s <width> <height> <infile> <outfile> <frame>\n",
  63           exec_name);
  64   exit(EXIT_FAILURE);
  65 }
  66
  67 static int encode_frame(vpx_codec_ctx_t *codec,
  68                         vpx_image_t *img,
  69                         int frame_index,
  70                         VpxVideoWriter *writer) {
  71   int got_pkts = 0;
  72   vpx_codec_iter_t iter = NULL;
  73   const vpx_codec_cx_pkt_t *pkt = NULL;
  74   const vpx_codec_err_t res = vpx_codec_encode(codec, img, frame_index, 1, 0,
  75                                                VPX_DL_GOOD_QUALITY);
  76   if (res != VPX_CODEC_OK)
  77     die_codec(codec, "Failed to encode frame");
  78
  79   while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) {
  80     got_pkts = 1;
  81
  82     if (pkt->kind == VPX_CODEC_CX_FRAME_PKT) {
  83       const int keyframe = (pkt->data.frame.flags & VPX_FRAME_IS_KEY) != 0;
  84       if (!vpx_video_writer_write_frame(writer,
  85                                         pkt->data.frame.buf,
  86                                         pkt->data.frame.sz,
  87                                         pkt->data.frame.pts)) {
  88         die_codec(codec, "Failed to write compressed frame");
  89       }
  90
  91       printf(keyframe ? "K" : ".");
  92       fflush(stdout);
  93     }
  94   }
  95
  96   return got_pkts;
  97 }
  98
  99 int main(int argc, char **argv) {
 100   FILE *infile = NULL;
 101   vpx_codec_ctx_t codec = {0};
 102   vpx_codec_enc_cfg_t cfg = {0};
 103   int frame_count = 0;
 104   vpx_image_t raw;
 105   vpx_codec_err_t res;
 106   VpxVideoInfo info = {0};
 107   VpxVideoWriter *writer = NULL;
 108   const VpxInterface *encoder = NULL;
 109   int update_frame_num = 0;
 110   const int fps = 30;        // TODO(dkovalev) add command line argument
 111   const int bitrate = 200;   // kbit/s TODO(dkovalev) add command line argument
 112
 113   exec_name = argv[0];
 114
 115   if (argc != 6)
 116     die("Invalid number of arguments");
 117
 118   // TODO(dkovalev): add vp9 support and rename the file accordingly
 119   encoder = get_vpx_encoder_by_name("vp8");
 120   if (!encoder)
 121     die("Unsupported codec.");
 122
 123   update_frame_num = atoi(argv[5]);
 124   if (!update_frame_num)
 125     die("Couldn't parse frame number '%s'\n", argv[5]);
 126
 127   info.codec_fourcc = encoder->fourcc;
 128   info.frame_width = strtol(argv[1], NULL, 0);
 129   info.frame_height = strtol(argv[2], NULL, 0);
 130   info.time_base.numerator = 1;
 131   info.time_base.denominator = fps;
 132
 133   if (info.frame_width <= 0 ||
 134       info.frame_height <= 0 ||
 135       (info.frame_width % 2) != 0 ||
 136       (info.frame_height % 2) != 0) {
 137     die("Invalid frame size: %dx%d", info.frame_width, info.frame_height);
 138   }
 139
 140   if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, info.frame_width,
 141                                              info.frame_height, 1)) {
 142     die("Failed to allocate image.");
 143   }
 144
 145   printf("Using %s\n", vpx_codec_iface_name(encoder->codec_interface()));
 146
 147   res = vpx_codec_enc_config_default(encoder->codec_interface(), &cfg, 0);
 148   if (res)
 149     die_codec(&codec, "Failed to get default codec config.");
 150
 151   cfg.g_w = info.frame_width;
 152   cfg.g_h = info.frame_height;
 153   cfg.g_timebase.num = info.time_base.numerator;
 154   cfg.g_timebase.den = info.time_base.denominator;
 155   cfg.rc_target_bitrate = bitrate;
 156
 157   writer = vpx_video_writer_open(argv[4], kContainerIVF, &info);
 158   if (!writer)
 159     die("Failed to open %s for writing.", argv[4]);
 160
 161   if (!(infile = fopen(argv[3], "rb")))
 162     die("Failed to open %s for reading.", argv[3]);
 163
 164   if (vpx_codec_enc_init(&codec, encoder->codec_interface(), &cfg, 0))
 165     die_codec(&codec, "Failed to initialize encoder");
 166
 167   // Encode frames.
 168   while (vpx_img_read(&raw, infile)) {
 169     if (frame_count + 1 == update_frame_num) {
 170       vpx_ref_frame_t ref;
 171       ref.frame_type = VP8_LAST_FRAME;
 172       ref.img = raw;
 173       if (vpx_codec_control(&codec, VP8_SET_REFERENCE, &ref))
 174         die_codec(&codec, "Failed to set reference frame");
 175     }
 176
 177     encode_frame(&codec, &raw, frame_count++, writer);
 178   }
 179
 180   // Flush encoder.
 181   while (encode_frame(&codec, NULL, -1, writer)) {}
 182
 183   printf("\n");
 184   fclose(infile);
 185   printf("Processed %d frames.\n", frame_count);
 186
 187   vpx_img_free(&raw);
 188   if (vpx_codec_destroy(&codec))
 189     die_codec(&codec, "Failed to destroy codec.");
 190
 191   vpx_video_writer_close(writer);
 192
 193   return EXIT_SUCCESS;
 194 }