ref: 2dad0e1238b67b97c2dab81fe181d5e19cd963be
dir: /examples/vp8cx_set_ref.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.
*/
// VP8 Set Reference Frame
// =======================
//
// This is an example demonstrating how to overwrite the VP8 encoder's
// internal reference frame. In the sample we set the last frame to the
// current frame. If this is done at a cut scene it will avoid a keyframe.
// This technique could be used to bounce between two cameras.
//
// Note that the decoder would also have to set the reference frame to the
// same value on the same frame, or the video will become corrupt.
//
// Usage
// -----
// This example adds a single argument to the `simple_encoder` example,
// which specifies the frame number to update the reference frame on.
// The parameter is parsed as follows:
//
//
// Extra Variables
// ---------------
// This example maintains the frame number passed on the command line
// in the `update_frame_num` variable.
//
//
// Configuration
// -------------
//
// The reference frame is updated on the frame specified on the command
// line.
//
// Observing The Effects
// ---------------------
// Use the `simple_encoder` example to encode a sample with a cut scene.
// Determine the frame number of the cut scene by looking for a generated
// key-frame (indicated by a 'K'). Supply that frame number as an argument
// to this example, and observe that no key-frame is generated.
#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, (unsigned int)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;
int update_frame_num = 0;
/* Open files */
if(argc!=6)
die("Usage: %s <width> <height> <infile> <outfile> <frame>\n",
argv[0]);
update_frame_num = atoi(argv[5]);
if(!update_frame_num)
die("Couldn't parse frame number '%s'\n", argv[5]);
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(frame_cnt + 1 == update_frame_num) {
vpx_ref_frame_t ref;
ref.frame_type = VP8_LAST_FRAME;
ref.img = raw;
if(vpx_codec_control(&codec, VP8_SET_REFERENCE, &ref))
die_codec(&codec, "Failed to set reference frame");
}
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;
}