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twopass_encoder.c (8186B)


      1 /*
      2 * Copyright (c) 2016, Alliance for Open Media. All rights reserved.
      3 *
      4 * This source code is subject to the terms of the BSD 2 Clause License and
      5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
      6 * was not distributed with this source code in the LICENSE file, you can
      7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
      8 * Media Patent License 1.0 was not distributed with this source code in the
      9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
     10 */
     11 
     12 // Two Pass Encoder
     13 // ================
     14 //
     15 // This is an example of a two pass encoder loop. It takes an input file in
     16 // YV12 format, passes it through the encoder twice, and writes the compressed
     17 // frames to disk in IVF format. It builds upon the simple_encoder example.
     18 //
     19 // Twopass Variables
     20 // -----------------
     21 // Twopass mode needs to track the current pass number and the buffer of
     22 // statistics packets.
     23 //
     24 // Updating The Configuration
     25 // ---------------------------------
     26 // In two pass mode, the configuration has to be updated on each pass. The
     27 // statistics buffer is passed on the last pass.
     28 //
     29 // Encoding A Frame
     30 // ----------------
     31 // Encoding a frame in two pass mode is identical to the simple encoder
     32 // example.
     33 //
     34 // Processing Statistics Packets
     35 // -----------------------------
     36 // Each packet of type `AOM_CODEC_CX_FRAME_PKT` contains the encoded data
     37 // for this frame. We write a IVF frame header, followed by the raw data.
     38 //
     39 //
     40 // Pass Progress Reporting
     41 // -----------------------------
     42 // It's sometimes helpful to see when each pass completes.
     43 //
     44 //
     45 // Clean-up
     46 // -----------------------------
     47 // Destruction of the encoder instance must be done on each pass. The
     48 // raw image should be destroyed at the end as usual.
     49 
     50 #include <stdio.h>
     51 #include <stdlib.h>
     52 #include <string.h>
     53 
     54 #include "aom/aom_encoder.h"
     55 #include "aom/aomcx.h"
     56 #include "common/tools_common.h"
     57 #include "common/video_writer.h"
     58 
     59 static const char *exec_name;
     60 
     61 void usage_exit(void) {
     62  fprintf(stderr,
     63          "Usage: %s <codec> <width> <height> <infile> <outfile> "
     64          "<limit(optional)>\n",
     65          exec_name);
     66  exit(EXIT_FAILURE);
     67 }
     68 
     69 static int get_frame_stats(aom_codec_ctx_t *ctx, const aom_image_t *img,
     70                           aom_codec_pts_t pts, unsigned int duration,
     71                           aom_enc_frame_flags_t flags,
     72                           aom_fixed_buf_t *stats) {
     73  int got_pkts = 0;
     74  aom_codec_iter_t iter = NULL;
     75  const aom_codec_cx_pkt_t *pkt = NULL;
     76  const aom_codec_err_t res = aom_codec_encode(ctx, img, pts, duration, flags);
     77  if (res != AOM_CODEC_OK) die_codec(ctx, "Failed to get frame stats.");
     78 
     79  while ((pkt = aom_codec_get_cx_data(ctx, &iter)) != NULL) {
     80    got_pkts = 1;
     81 
     82    if (pkt->kind == AOM_CODEC_STATS_PKT) {
     83      const uint8_t *const pkt_buf = pkt->data.twopass_stats.buf;
     84      const size_t pkt_size = pkt->data.twopass_stats.sz;
     85      stats->buf = realloc(stats->buf, stats->sz + pkt_size);
     86      if (!stats->buf) die("Failed to allocate frame stats buffer.");
     87      memcpy((uint8_t *)stats->buf + stats->sz, pkt_buf, pkt_size);
     88      stats->sz += pkt_size;
     89    }
     90  }
     91 
     92  return got_pkts;
     93 }
     94 
     95 static int encode_frame(aom_codec_ctx_t *ctx, const aom_image_t *img,
     96                        aom_codec_pts_t pts, unsigned int duration,
     97                        aom_enc_frame_flags_t flags, AvxVideoWriter *writer) {
     98  int got_pkts = 0;
     99  aom_codec_iter_t iter = NULL;
    100  const aom_codec_cx_pkt_t *pkt = NULL;
    101  const aom_codec_err_t res = aom_codec_encode(ctx, img, pts, duration, flags);
    102  if (res != AOM_CODEC_OK) die_codec(ctx, "Failed to encode frame.");
    103 
    104  while ((pkt = aom_codec_get_cx_data(ctx, &iter)) != NULL) {
    105    got_pkts = 1;
    106    if (pkt->kind == AOM_CODEC_CX_FRAME_PKT) {
    107      const int keyframe = (pkt->data.frame.flags & AOM_FRAME_IS_KEY) != 0;
    108 
    109      if (!aom_video_writer_write_frame(writer, pkt->data.frame.buf,
    110                                        pkt->data.frame.sz,
    111                                        pkt->data.frame.pts))
    112        die_codec(ctx, "Failed to write compressed frame.");
    113      printf(keyframe ? "K" : ".");
    114      fflush(stdout);
    115    }
    116  }
    117 
    118  return got_pkts;
    119 }
    120 
    121 static aom_fixed_buf_t pass0(aom_image_t *raw, FILE *infile,
    122                             aom_codec_iface_t *encoder,
    123                             const aom_codec_enc_cfg_t *cfg, int limit) {
    124  aom_codec_ctx_t codec;
    125  int frame_count = 0;
    126  aom_fixed_buf_t stats = { NULL, 0 };
    127 
    128  if (aom_codec_enc_init(&codec, encoder, cfg, 0))
    129    die("Failed to initialize encoder");
    130 
    131  // Calculate frame statistics.
    132  while (aom_img_read(raw, infile) && frame_count < limit) {
    133    ++frame_count;
    134    get_frame_stats(&codec, raw, frame_count, 1, 0, &stats);
    135  }
    136 
    137  // Flush encoder.
    138  while (get_frame_stats(&codec, NULL, frame_count, 1, 0, &stats)) {
    139  }
    140 
    141  printf("Pass 0 complete. Processed %d frames.\n", frame_count);
    142  if (aom_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec.");
    143 
    144  return stats;
    145 }
    146 
    147 static void pass1(aom_image_t *raw, FILE *infile, const char *outfile_name,
    148                  aom_codec_iface_t *encoder, const aom_codec_enc_cfg_t *cfg,
    149                  int limit) {
    150  AvxVideoInfo info = { get_fourcc_by_aom_encoder(encoder),
    151                        cfg->g_w,
    152                        cfg->g_h,
    153                        { cfg->g_timebase.num, cfg->g_timebase.den },
    154                        0 };
    155  AvxVideoWriter *writer = NULL;
    156  aom_codec_ctx_t codec;
    157  int frame_count = 0;
    158 
    159  writer = aom_video_writer_open(outfile_name, kContainerIVF, &info);
    160  if (!writer) die("Failed to open %s for writing", outfile_name);
    161 
    162  if (aom_codec_enc_init(&codec, encoder, cfg, 0))
    163    die("Failed to initialize encoder");
    164 
    165  if (aom_codec_control(&codec, AOME_SET_CPUUSED, 2))
    166    die_codec(&codec, "Failed to set cpu-used");
    167 
    168  // Encode frames.
    169  while (aom_img_read(raw, infile) && frame_count < limit) {
    170    ++frame_count;
    171    encode_frame(&codec, raw, frame_count, 1, 0, writer);
    172  }
    173 
    174  // Flush encoder.
    175  while (encode_frame(&codec, NULL, -1, 1, 0, writer)) {
    176  }
    177 
    178  printf("\n");
    179 
    180  if (aom_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec.");
    181 
    182  aom_video_writer_close(writer);
    183 
    184  printf("Pass 1 complete. Processed %d frames.\n", frame_count);
    185 }
    186 
    187 int main(int argc, char **argv) {
    188  FILE *infile = NULL;
    189  int w, h;
    190  aom_codec_ctx_t codec;
    191  aom_codec_enc_cfg_t cfg;
    192  aom_image_t raw;
    193  aom_codec_err_t res;
    194  aom_fixed_buf_t stats;
    195 
    196  const int fps = 30;       // TODO(dkovalev) add command line argument
    197  const int bitrate = 200;  // kbit/s TODO(dkovalev) add command line argument
    198  const char *const codec_arg = argv[1];
    199  const char *const width_arg = argv[2];
    200  const char *const height_arg = argv[3];
    201  const char *const infile_arg = argv[4];
    202  const char *const outfile_arg = argv[5];
    203  int limit = 0;
    204  exec_name = argv[0];
    205 
    206  if (argc < 6) die("Invalid number of arguments");
    207 
    208  if (argc > 6) limit = (int)strtol(argv[6], NULL, 0);
    209 
    210  if (limit == 0) limit = 100;
    211 
    212  aom_codec_iface_t *encoder = get_aom_encoder_by_short_name(codec_arg);
    213  if (!encoder) die("Unsupported codec.");
    214 
    215  w = (int)strtol(width_arg, NULL, 0);
    216  h = (int)strtol(height_arg, NULL, 0);
    217 
    218  if (w <= 0 || h <= 0 || (w % 2) != 0 || (h % 2) != 0)
    219    die("Invalid frame size: %dx%d", w, h);
    220 
    221  if (!aom_img_alloc(&raw, AOM_IMG_FMT_I420, w, h, 1))
    222    die("Failed to allocate image (%dx%d)", w, h);
    223 
    224  printf("Using %s\n", aom_codec_iface_name(encoder));
    225 
    226  // Configuration
    227  res = aom_codec_enc_config_default(encoder, &cfg, 0);
    228  if (res) die_codec(&codec, "Failed to get default codec config.");
    229 
    230  cfg.g_w = w;
    231  cfg.g_h = h;
    232  cfg.g_timebase.num = 1;
    233  cfg.g_timebase.den = fps;
    234  cfg.rc_target_bitrate = bitrate;
    235 
    236  if (!(infile = fopen(infile_arg, "rb")))
    237    die("Failed to open %s for reading", infile_arg);
    238 
    239  // Pass 0
    240  cfg.g_pass = AOM_RC_FIRST_PASS;
    241  stats = pass0(&raw, infile, encoder, &cfg, limit);
    242 
    243  // Pass 1
    244  rewind(infile);
    245  cfg.g_pass = AOM_RC_LAST_PASS;
    246  cfg.rc_twopass_stats_in = stats;
    247  pass1(&raw, infile, outfile_arg, encoder, &cfg, limit);
    248  free(stats.buf);
    249 
    250  aom_img_free(&raw);
    251  fclose(infile);
    252 
    253  return EXIT_SUCCESS;
    254 }