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/* *  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. */ // Simple Encoder// ==============//// This is an example of a simple encoder loop. It takes an input file in// YV12 format, passes it through the encoder, and writes the compressed// frames to disk in IVF format. Other decoder examples build upon this// one.//// The details of the IVF format have been elided from this example for// simplicity of presentation, as IVF files will not generally be used by// your application. In general, an IVF file consists of a file header,// followed by a variable number of frames. Each frame consists of a frame// header followed by a variable length payload. The length of the payload// is specified in the first four bytes of the frame header. The payload is// the raw compressed data.//// Standard Includes// -----------------// For encoders, you only have to include `vpx_encoder.h` and then any// header files for the specific codecs you use. In this case, we're using// vp8.//// Getting The Default Configuration// ---------------------------------// Encoders have the notion of "usage profiles." For example, an encoder// may want to publish default configurations for both a video// conferencing application and a best quality offline encoder. These// obviously have very different default settings. Consult the// documentation for your codec to see if it provides any default// configurations. All codecs provide a default configuration, number 0,// which is valid for material in the vacinity of QCIF/QVGA.//// Updating The Configuration// ---------------------------------// Almost all applications will want to update the default configuration// with settings specific to their usage. Here we set the width and height// of the video file to that specified on the command line. We also scale// the default bitrate based on the ratio between the default resolution// and the resolution specified on the command line.//// Initializing The Codec// ----------------------// The encoder is initialized by the following code.//// Encoding A Frame// ----------------// The frame is read as a continuous block (size width * height * 3 / 2)// from the input file. If a frame was read (the input file has not hit// EOF) then the frame is passed to the encoder. Otherwise, a NULL// is passed, indicating the End-Of-Stream condition to the encoder. The// `frame_cnt` is reused as the presentation time stamp (PTS) and each// frame is shown for one frame-time in duration. The flags parameter is// unused in this example. The deadline is set to VPX_DL_REALTIME to// make the example run as quickly as possible. // Forced Keyframes// ----------------// Keyframes can be forced by setting the VPX_EFLAG_FORCE_KF bit of the// flags passed to `vpx_codec_control()`. In this example, we force a// keyframe every <keyframe-interval> frames. Note, the output stream can// contain additional keyframes beyond those that have been forced using the// VPX_EFLAG_FORCE_KF flag because of automatic keyframe placement by the// encoder.//// Processing The Encoded Data// ---------------------------// Each packet of type `VPX_CODEC_CX_FRAME_PKT` contains the encoded data// for this frame. We write a IVF frame header, followed by the raw data.//// Cleanup// -------// The `vpx_codec_destroy` call frees any memory allocated by the codec.//// Error Handling// --------------// This example does not special case any error return codes. If there was// an error, a descriptive message is printed and the program exits. With// few exeptions, vpx_codec functions return an enumerated error status,// with the value `0` indicating success.//// Error Resiliency Features// -------------------------// Error resiliency is controlled by the g_error_resilient member of the// configuration structure. Use the `decode_with_drops` example to decode with// frames 5-10 dropped. Compare the output for a file encoded with this example// versus one encoded with the `simple_encoder` example. #include <stdio.h>#include <stdlib.h>#include <string.h> #include "vpx/vpx_encoder.h" #include "../tools_common.h"#include "../video_writer.h" static const char *exec_name; void usage_exit(void) {  fprintf(stderr,          "Usage: %s <codec> <width> <height> <infile> <outfile> "          "<keyframe-interval> <error-resilient> <frames to encode>\n"          "See comments in simple_encoder.c for more information.\n",          exec_name);  exit(EXIT_FAILURE);} static int encode_frame(vpx_codec_ctx_t *codec, vpx_image_t *img,                        int frame_index, int flags, VpxVideoWriter *writer) {  int got_pkts = 0;  vpx_codec_iter_t iter = NULL;  const vpx_codec_cx_pkt_t *pkt = NULL;  const vpx_codec_err_t res =      vpx_codec_encode(codec, img, frame_index, 1, flags, VPX_DL_GOOD_QUALITY);  if (res != VPX_CODEC_OK) die_codec(codec, "Failed to encode frame");   while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) {    got_pkts = 1;     if (pkt->kind == VPX_CODEC_CX_FRAME_PKT) {      const int keyframe = (pkt->data.frame.flags & VPX_FRAME_IS_KEY) != 0;      if (!vpx_video_writer_write_frame(writer, pkt->data.frame.buf,                                        pkt->data.frame.sz,                                        pkt->data.frame.pts)) {        die_codec(codec, "Failed to write compressed frame");      }      printf(keyframe ? "K" : ".");      fflush(stdout);    }  }   return got_pkts;} // TODO(tomfinegan): Improve command line parsing and add args for bitrate/fps.int main(int argc, char **argv) {  FILE *infile = NULL;  vpx_codec_ctx_t codec;  vpx_codec_enc_cfg_t cfg;  int frame_count = 0;  vpx_image_t raw;  vpx_codec_err_t res;  VpxVideoInfo info = { 0, 0, 0, { 0, 0 } };  VpxVideoWriter *writer = NULL;  const VpxInterface *encoder = NULL;  const int fps = 30;  const int bitrate = 200;  int keyframe_interval = 0;  int max_frames = 0;  int frames_encoded = 0;  const char *codec_arg = NULL;  const char *width_arg = NULL;  const char *height_arg = NULL;  const char *infile_arg = NULL;  const char *outfile_arg = NULL;  const char *keyframe_interval_arg = NULL;   exec_name = argv[0];   if (argc != 9) die("Invalid number of arguments");   codec_arg = argv[1];  width_arg = argv[2];  height_arg = argv[3];  infile_arg = argv[4];  outfile_arg = argv[5];  keyframe_interval_arg = argv[6];  max_frames = (int)strtol(argv[8], NULL, 0);   encoder = get_vpx_encoder_by_name(codec_arg);  if (!encoder) die("Unsupported codec.");   info.codec_fourcc = encoder->fourcc;  info.frame_width = (int)strtol(width_arg, NULL, 0);  info.frame_height = (int)strtol(height_arg, NULL, 0);  info.time_base.numerator = 1;  info.time_base.denominator = fps;   if (info.frame_width <= 0 || info.frame_height <= 0 ||      (info.frame_width % 2) != 0 || (info.frame_height % 2) != 0) {    die("Invalid frame size: %dx%d", info.frame_width, info.frame_height);  }   if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, info.frame_width,                     info.frame_height, 1)) {    die("Failed to allocate image.");  }   keyframe_interval = (int)strtol(keyframe_interval_arg, NULL, 0);  if (keyframe_interval < 0) die("Invalid keyframe interval value.");   printf("Using %s\n", vpx_codec_iface_name(encoder->codec_interface()));   res = vpx_codec_enc_config_default(encoder->codec_interface(), &cfg, 0);  if (res) die_codec(&codec, "Failed to get default codec config.");   cfg.g_w = info.frame_width;  cfg.g_h = info.frame_height;  cfg.g_timebase.num = info.time_base.numerator;  cfg.g_timebase.den = info.time_base.denominator;  cfg.rc_target_bitrate = bitrate;  cfg.g_error_resilient = (vpx_codec_er_flags_t)strtoul(argv[7], NULL, 0);   writer = vpx_video_writer_open(outfile_arg, kContainerIVF, &info);  if (!writer) die("Failed to open %s for writing.", outfile_arg);   if (!(infile = fopen(infile_arg, "rb")))    die("Failed to open %s for reading.", infile_arg);   if (vpx_codec_enc_init(&codec, encoder->codec_interface(), &cfg, 0))    die("Failed to initialize encoder");   // Encode frames.  while (vpx_img_read(&raw, infile)) {    int flags = 0;    if (keyframe_interval > 0 && frame_count % keyframe_interval == 0)      flags |= VPX_EFLAG_FORCE_KF;    encode_frame(&codec, &raw, frame_count++, flags, writer);    frames_encoded++;    if (max_frames > 0 && frames_encoded >= max_frames) break;  }   // Flush encoder.  while (encode_frame(&codec, NULL, -1, 0, writer)) {  }   printf("\n");  fclose(infile);  printf("Processed %d frames.\n", frame_count);   vpx_img_free(&raw);  if (vpx_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec.");   vpx_video_writer_close(writer);   return EXIT_SUCCESS;}

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