ref: 6253e8ed477a2a529cd321a7c3d244996fd026fa
dir: /examples/simple_encoder.c/
/*
* 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. The `VPX_CODEC_DISABLE_COMPAT` macro can be defined to ensure
// strict compliance with the latest SDK by disabling some backwards
// compatibility features. Defining this macro is encouraged.
//
// 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 appliction 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.
//
// 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.
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#define VPX_CODEC_DISABLE_COMPAT 1
#include "vpx/vpx_encoder.h"
#include "vpx/vp8cx.h"
#define interface (vpx_codec_vp8_cx())
#define fourcc 0x30385056
#define IVF_FILE_HDR_SZ (32)
#define IVF_FRAME_HDR_SZ (12)
static void mem_put_le16(char *mem, unsigned int val) {
mem[0] = val;
mem[1] = val>>8;
}
static void mem_put_le32(char *mem, unsigned int val) {
mem[0] = val;
mem[1] = val>>8;
mem[2] = val>>16;
mem[3] = val>>24;
}
static void die(const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
vprintf(fmt, ap);
if(fmt[strlen(fmt)-1] != '\n')
printf("\n");
exit(EXIT_FAILURE);
}
static void die_codec(vpx_codec_ctx_t *ctx, const char *s) {
const char *detail = vpx_codec_error_detail(ctx);
printf("%s: %s\n", s, vpx_codec_error(ctx));
if(detail)
printf(" %s\n",detail);
exit(EXIT_FAILURE);
}
static int read_frame(FILE *f, vpx_image_t *img) {
size_t nbytes, to_read;
int res = 1;
to_read = img->w*img->h*3/2;
nbytes = fread(img->planes[0], 1, to_read, f);
if(nbytes != to_read) {
res = 0;
if(nbytes > 0)
printf("Warning: Read partial frame. Check your width & height!\n");
}
return res;
}
static void write_ivf_file_header(FILE *outfile,
const vpx_codec_enc_cfg_t *cfg,
int frame_cnt) {
char header[32];
if(cfg->g_pass != VPX_RC_ONE_PASS && cfg->g_pass != VPX_RC_LAST_PASS)
return;
header[0] = 'D';
header[1] = 'K';
header[2] = 'I';
header[3] = 'F';
mem_put_le16(header+4, 0); /* version */
mem_put_le16(header+6, 32); /* headersize */
mem_put_le32(header+8, fourcc); /* headersize */
mem_put_le16(header+12, cfg->g_w); /* width */
mem_put_le16(header+14, cfg->g_h); /* height */
mem_put_le32(header+16, cfg->g_timebase.den); /* rate */
mem_put_le32(header+20, cfg->g_timebase.num); /* scale */
mem_put_le32(header+24, frame_cnt); /* length */
mem_put_le32(header+28, 0); /* unused */
(void) fwrite(header, 1, 32, outfile);
}
static void write_ivf_frame_header(FILE *outfile,
const vpx_codec_cx_pkt_t *pkt)
{
char header[12];
vpx_codec_pts_t pts;
if(pkt->kind != VPX_CODEC_CX_FRAME_PKT)
return;
pts = pkt->data.frame.pts;
mem_put_le32(header, pkt->data.frame.sz);
mem_put_le32(header+4, pts&0xFFFFFFFF);
mem_put_le32(header+8, pts >> 32);
(void) fwrite(header, 1, 12, outfile);
}
int main(int argc, char **argv) {
FILE *infile, *outfile;
vpx_codec_ctx_t codec;
vpx_codec_enc_cfg_t cfg;
int frame_cnt = 0;
vpx_image_t raw;
vpx_codec_err_t res;
long width;
long height;
int frame_avail;
int got_data;
int flags = 0;
/* Open files */
if(argc!=5)
die("Usage: %s <width> <height> <infile> <outfile>\n", argv[0]);
width = strtol(argv[1], NULL, 0);
height = strtol(argv[2], NULL, 0);
if(width < 16 || width%2 || height <16 || height%2)
die("Invalid resolution: %ldx%ld", width, height);
if(!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, width, height, 1))
die("Faile to allocate image", width, height);
if(!(outfile = fopen(argv[4], "wb")))
die("Failed to open %s for writing", argv[4]);
printf("Using %s\n",vpx_codec_iface_name(interface));
/* Populate encoder configuration */
res = vpx_codec_enc_config_default(interface, &cfg, 0);
if(res) {
printf("Failed to get config: %s\n", vpx_codec_err_to_string(res));
return EXIT_FAILURE;
}
/* Update the default configuration with our settings */
cfg.rc_target_bitrate = width * height * cfg.rc_target_bitrate
/ cfg.g_w / cfg.g_h;
cfg.g_w = width;
cfg.g_h = height;
write_ivf_file_header(outfile, &cfg, 0);
/* Open input file for this encoding pass */
if(!(infile = fopen(argv[3], "rb")))
die("Failed to open %s for reading", argv[3]);
/* Initialize codec */
if(vpx_codec_enc_init(&codec, interface, &cfg, 0))
die_codec(&codec, "Failed to initialize encoder");
frame_avail = 1;
got_data = 0;
while(frame_avail || got_data) {
vpx_codec_iter_t iter = NULL;
const vpx_codec_cx_pkt_t *pkt;
frame_avail = read_frame(infile, &raw);
if(vpx_codec_encode(&codec, frame_avail? &raw : NULL, frame_cnt,
1, flags, VPX_DL_REALTIME))
die_codec(&codec, "Failed to encode frame");
got_data = 0;
while( (pkt = vpx_codec_get_cx_data(&codec, &iter)) ) {
got_data = 1;
switch(pkt->kind) {
case VPX_CODEC_CX_FRAME_PKT:
write_ivf_frame_header(outfile, pkt);
(void) fwrite(pkt->data.frame.buf, 1, pkt->data.frame.sz,
outfile);
break;
default:
break;
}
printf(pkt->kind == VPX_CODEC_CX_FRAME_PKT
&& (pkt->data.frame.flags & VPX_FRAME_IS_KEY)? "K":".");
fflush(stdout);
}
frame_cnt++;
}
printf("\n");
fclose(infile);
printf("Processed %d frames.\n",frame_cnt-1);
vpx_img_free(&raw);
if(vpx_codec_destroy(&codec))
die_codec(&codec, "Failed to destroy codec");
/* Try to rewrite the file header with the actual frame count */
if(!fseek(outfile, 0, SEEK_SET))
write_ivf_file_header(outfile, &cfg, frame_cnt-1);
fclose(outfile);
return EXIT_SUCCESS;
}