mirror of https://git.ffmpeg.org/ffmpeg.git
537 lines
16 KiB
C
537 lines
16 KiB
C
/*
|
|
* Copyright (c) 2003 Fabrice Bellard
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* libavformat API example.
|
|
*
|
|
* @example output.c
|
|
* Output a media file in any supported libavformat format. The default
|
|
* codecs are used.
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <math.h>
|
|
|
|
#include "libavutil/channel_layout.h"
|
|
#include "libavutil/mathematics.h"
|
|
#include "libavformat/avformat.h"
|
|
#include "libswscale/swscale.h"
|
|
|
|
/* 5 seconds stream duration */
|
|
#define STREAM_DURATION 5.0
|
|
#define STREAM_FRAME_RATE 25 /* 25 images/s */
|
|
#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * STREAM_FRAME_RATE))
|
|
#define STREAM_PIX_FMT AV_PIX_FMT_YUV420P /* default pix_fmt */
|
|
|
|
static int sws_flags = SWS_BICUBIC;
|
|
|
|
// a wrapper around a single output AVStream
|
|
typedef struct OutputStream {
|
|
AVStream *st;
|
|
|
|
AVFrame *frame;
|
|
AVFrame *tmp_frame;
|
|
} OutputStream;
|
|
|
|
/**************************************************************/
|
|
/* audio output */
|
|
|
|
static float t, tincr, tincr2;
|
|
static int16_t *samples;
|
|
static int audio_input_frame_size;
|
|
|
|
/*
|
|
* add an audio output stream
|
|
*/
|
|
static AVStream *add_audio_stream(AVFormatContext *oc, enum AVCodecID codec_id)
|
|
{
|
|
AVCodecContext *c;
|
|
AVStream *st;
|
|
AVCodec *codec;
|
|
|
|
/* find the audio encoder */
|
|
codec = avcodec_find_encoder(codec_id);
|
|
if (!codec) {
|
|
fprintf(stderr, "codec not found\n");
|
|
exit(1);
|
|
}
|
|
|
|
st = avformat_new_stream(oc, codec);
|
|
if (!st) {
|
|
fprintf(stderr, "Could not alloc stream\n");
|
|
exit(1);
|
|
}
|
|
|
|
c = st->codec;
|
|
|
|
/* put sample parameters */
|
|
c->sample_fmt = AV_SAMPLE_FMT_S16;
|
|
c->bit_rate = 64000;
|
|
c->sample_rate = 44100;
|
|
c->channels = 2;
|
|
c->channel_layout = AV_CH_LAYOUT_STEREO;
|
|
|
|
// some formats want stream headers to be separate
|
|
if (oc->oformat->flags & AVFMT_GLOBALHEADER)
|
|
c->flags |= CODEC_FLAG_GLOBAL_HEADER;
|
|
|
|
return st;
|
|
}
|
|
|
|
static void open_audio(AVFormatContext *oc, AVStream *st)
|
|
{
|
|
AVCodecContext *c;
|
|
|
|
c = st->codec;
|
|
|
|
/* open it */
|
|
if (avcodec_open2(c, NULL, NULL) < 0) {
|
|
fprintf(stderr, "could not open codec\n");
|
|
exit(1);
|
|
}
|
|
|
|
/* init signal generator */
|
|
t = 0;
|
|
tincr = 2 * M_PI * 110.0 / c->sample_rate;
|
|
/* increment frequency by 110 Hz per second */
|
|
tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
|
|
|
|
if (c->codec->capabilities & CODEC_CAP_VARIABLE_FRAME_SIZE)
|
|
audio_input_frame_size = 10000;
|
|
else
|
|
audio_input_frame_size = c->frame_size;
|
|
samples = av_malloc(audio_input_frame_size *
|
|
av_get_bytes_per_sample(c->sample_fmt) *
|
|
c->channels);
|
|
}
|
|
|
|
/* Prepare a 16 bit dummy audio frame of 'frame_size' samples and
|
|
* 'nb_channels' channels. */
|
|
static void get_audio_frame(int16_t *samples, int frame_size, int nb_channels)
|
|
{
|
|
int j, i, v;
|
|
int16_t *q;
|
|
|
|
q = samples;
|
|
for (j = 0; j < frame_size; j++) {
|
|
v = (int)(sin(t) * 10000);
|
|
for (i = 0; i < nb_channels; i++)
|
|
*q++ = v;
|
|
t += tincr;
|
|
tincr += tincr2;
|
|
}
|
|
}
|
|
|
|
static void write_audio_frame(AVFormatContext *oc, AVStream *st)
|
|
{
|
|
AVCodecContext *c;
|
|
AVPacket pkt = { 0 }; // data and size must be 0;
|
|
AVFrame *frame = av_frame_alloc();
|
|
int got_packet;
|
|
|
|
av_init_packet(&pkt);
|
|
c = st->codec;
|
|
|
|
get_audio_frame(samples, audio_input_frame_size, c->channels);
|
|
frame->nb_samples = audio_input_frame_size;
|
|
avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
|
|
(uint8_t *)samples,
|
|
audio_input_frame_size *
|
|
av_get_bytes_per_sample(c->sample_fmt) *
|
|
c->channels, 1);
|
|
|
|
avcodec_encode_audio2(c, &pkt, frame, &got_packet);
|
|
if (!got_packet)
|
|
return;
|
|
|
|
pkt.stream_index = st->index;
|
|
|
|
/* Write the compressed frame to the media file. */
|
|
if (av_interleaved_write_frame(oc, &pkt) != 0) {
|
|
fprintf(stderr, "Error while writing audio frame\n");
|
|
exit(1);
|
|
}
|
|
av_frame_free(&frame);
|
|
}
|
|
|
|
static void close_audio(AVFormatContext *oc, AVStream *st)
|
|
{
|
|
avcodec_close(st->codec);
|
|
|
|
av_free(samples);
|
|
}
|
|
|
|
/**************************************************************/
|
|
/* video output */
|
|
|
|
static int frame_count;
|
|
|
|
/* Add a video output stream. */
|
|
static void add_video_stream(OutputStream *ost, AVFormatContext *oc,
|
|
enum AVCodecID codec_id)
|
|
{
|
|
AVCodecContext *c;
|
|
AVCodec *codec;
|
|
|
|
/* find the video encoder */
|
|
codec = avcodec_find_encoder(codec_id);
|
|
if (!codec) {
|
|
fprintf(stderr, "codec not found\n");
|
|
exit(1);
|
|
}
|
|
|
|
ost->st = avformat_new_stream(oc, codec);
|
|
if (!ost->st) {
|
|
fprintf(stderr, "Could not alloc stream\n");
|
|
exit(1);
|
|
}
|
|
|
|
c = ost->st->codec;
|
|
|
|
/* Put sample parameters. */
|
|
c->bit_rate = 400000;
|
|
/* Resolution must be a multiple of two. */
|
|
c->width = 352;
|
|
c->height = 288;
|
|
/* timebase: This is the fundamental unit of time (in seconds) in terms
|
|
* of which frame timestamps are represented. For fixed-fps content,
|
|
* timebase should be 1/framerate and timestamp increments should be
|
|
* identical to 1. */
|
|
c->time_base.den = STREAM_FRAME_RATE;
|
|
c->time_base.num = 1;
|
|
c->gop_size = 12; /* emit one intra frame every twelve frames at most */
|
|
c->pix_fmt = STREAM_PIX_FMT;
|
|
if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
|
|
/* just for testing, we also add B frames */
|
|
c->max_b_frames = 2;
|
|
}
|
|
if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
|
|
/* Needed to avoid using macroblocks in which some coeffs overflow.
|
|
* This does not happen with normal video, it just happens here as
|
|
* the motion of the chroma plane does not match the luma plane. */
|
|
c->mb_decision = 2;
|
|
}
|
|
/* Some formats want stream headers to be separate. */
|
|
if (oc->oformat->flags & AVFMT_GLOBALHEADER)
|
|
c->flags |= CODEC_FLAG_GLOBAL_HEADER;
|
|
}
|
|
|
|
static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
|
|
{
|
|
AVFrame *picture;
|
|
int ret;
|
|
|
|
picture = av_frame_alloc();
|
|
if (!picture)
|
|
return NULL;
|
|
|
|
picture->format = pix_fmt;
|
|
picture->width = width;
|
|
picture->height = height;
|
|
|
|
/* allocate the buffers for the frame data */
|
|
ret = av_frame_get_buffer(picture, 32);
|
|
if (ret < 0) {
|
|
fprintf(stderr, "Could not allocate frame data.\n");
|
|
exit(1);
|
|
}
|
|
|
|
return picture;
|
|
}
|
|
|
|
static void open_video(AVFormatContext *oc, OutputStream *ost)
|
|
{
|
|
AVCodecContext *c;
|
|
|
|
c = ost->st->codec;
|
|
|
|
/* open the codec */
|
|
if (avcodec_open2(c, NULL, NULL) < 0) {
|
|
fprintf(stderr, "could not open codec\n");
|
|
exit(1);
|
|
}
|
|
|
|
/* Allocate the encoded raw picture. */
|
|
ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
|
|
if (!ost->frame) {
|
|
fprintf(stderr, "Could not allocate picture\n");
|
|
exit(1);
|
|
}
|
|
|
|
/* If the output format is not YUV420P, then a temporary YUV420P
|
|
* picture is needed too. It is then converted to the required
|
|
* output format. */
|
|
ost->tmp_frame = NULL;
|
|
if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
|
|
ost->tmp_frame = alloc_picture(AV_PIX_FMT_YUV420P, c->width, c->height);
|
|
if (!ost->tmp_frame) {
|
|
fprintf(stderr, "Could not allocate temporary picture\n");
|
|
exit(1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Prepare a dummy image. */
|
|
static void fill_yuv_image(AVFrame *pict, int frame_index,
|
|
int width, int height)
|
|
{
|
|
int x, y, i, ret;
|
|
|
|
/* when we pass a frame to the encoder, it may keep a reference to it
|
|
* internally;
|
|
* make sure we do not overwrite it here
|
|
*/
|
|
ret = av_frame_make_writable(pict);
|
|
if (ret < 0)
|
|
exit(1);
|
|
|
|
i = frame_index;
|
|
|
|
/* Y */
|
|
for (y = 0; y < height; y++)
|
|
for (x = 0; x < width; x++)
|
|
pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
|
|
|
|
/* Cb and Cr */
|
|
for (y = 0; y < height / 2; y++) {
|
|
for (x = 0; x < width / 2; x++) {
|
|
pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
|
|
pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void write_video_frame(AVFormatContext *oc, OutputStream *ost)
|
|
{
|
|
int ret;
|
|
AVCodecContext *c;
|
|
static struct SwsContext *img_convert_ctx;
|
|
|
|
c = ost->st->codec;
|
|
|
|
if (frame_count >= STREAM_NB_FRAMES) {
|
|
/* No more frames to compress. The codec has a latency of a few
|
|
* frames if using B-frames, so we get the last frames by
|
|
* passing the same picture again. */
|
|
} else {
|
|
if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
|
|
/* as we only generate a YUV420P picture, we must convert it
|
|
* to the codec pixel format if needed */
|
|
if (img_convert_ctx == NULL) {
|
|
img_convert_ctx = sws_getContext(c->width, c->height,
|
|
AV_PIX_FMT_YUV420P,
|
|
c->width, c->height,
|
|
c->pix_fmt,
|
|
sws_flags, NULL, NULL, NULL);
|
|
if (img_convert_ctx == NULL) {
|
|
fprintf(stderr,
|
|
"Cannot initialize the conversion context\n");
|
|
exit(1);
|
|
}
|
|
}
|
|
fill_yuv_image(ost->tmp_frame, frame_count, c->width, c->height);
|
|
sws_scale(img_convert_ctx, ost->tmp_frame->data, ost->tmp_frame->linesize,
|
|
0, c->height, ost->frame->data, ost->frame->linesize);
|
|
} else {
|
|
fill_yuv_image(ost->frame, frame_count, c->width, c->height);
|
|
}
|
|
}
|
|
|
|
if (oc->oformat->flags & AVFMT_RAWPICTURE) {
|
|
/* Raw video case - the API will change slightly in the near
|
|
* future for that. */
|
|
AVPacket pkt;
|
|
av_init_packet(&pkt);
|
|
|
|
pkt.flags |= AV_PKT_FLAG_KEY;
|
|
pkt.stream_index = ost->st->index;
|
|
pkt.data = (uint8_t *)ost->frame;
|
|
pkt.size = sizeof(AVPicture);
|
|
|
|
ret = av_interleaved_write_frame(oc, &pkt);
|
|
} else {
|
|
AVPacket pkt = { 0 };
|
|
int got_packet;
|
|
av_init_packet(&pkt);
|
|
|
|
/* encode the image */
|
|
ret = avcodec_encode_video2(c, &pkt, ost->frame, &got_packet);
|
|
/* If size is zero, it means the image was buffered. */
|
|
if (!ret && got_packet && pkt.size) {
|
|
av_packet_rescale_ts(&pkt, c->time_base, ost->st->time_base);
|
|
pkt.stream_index = ost->st->index;
|
|
|
|
/* Write the compressed frame to the media file. */
|
|
ret = av_interleaved_write_frame(oc, &pkt);
|
|
} else {
|
|
ret = 0;
|
|
}
|
|
}
|
|
if (ret != 0) {
|
|
fprintf(stderr, "Error while writing video frame\n");
|
|
exit(1);
|
|
}
|
|
frame_count++;
|
|
}
|
|
|
|
static void close_video(AVFormatContext *oc, OutputStream *ost)
|
|
{
|
|
avcodec_close(ost->st->codec);
|
|
av_frame_free(&ost->frame);
|
|
av_frame_free(&ost->tmp_frame);
|
|
}
|
|
|
|
/**************************************************************/
|
|
/* media file output */
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
OutputStream video_st;
|
|
const char *filename;
|
|
AVOutputFormat *fmt;
|
|
AVFormatContext *oc;
|
|
AVStream *audio_st;
|
|
double audio_pts, video_pts;
|
|
int have_video = 0;
|
|
int i;
|
|
|
|
/* Initialize libavcodec, and register all codecs and formats. */
|
|
av_register_all();
|
|
|
|
if (argc != 2) {
|
|
printf("usage: %s output_file\n"
|
|
"API example program to output a media file with libavformat.\n"
|
|
"The output format is automatically guessed according to the file extension.\n"
|
|
"Raw images can also be output by using '%%d' in the filename\n"
|
|
"\n", argv[0]);
|
|
return 1;
|
|
}
|
|
|
|
filename = argv[1];
|
|
|
|
/* Autodetect the output format from the name. default is MPEG. */
|
|
fmt = av_guess_format(NULL, filename, NULL);
|
|
if (!fmt) {
|
|
printf("Could not deduce output format from file extension: using MPEG.\n");
|
|
fmt = av_guess_format("mpeg", NULL, NULL);
|
|
}
|
|
if (!fmt) {
|
|
fprintf(stderr, "Could not find suitable output format\n");
|
|
return 1;
|
|
}
|
|
|
|
/* Allocate the output media context. */
|
|
oc = avformat_alloc_context();
|
|
if (!oc) {
|
|
fprintf(stderr, "Memory error\n");
|
|
return 1;
|
|
}
|
|
oc->oformat = fmt;
|
|
snprintf(oc->filename, sizeof(oc->filename), "%s", filename);
|
|
|
|
/* Add the audio and video streams using the default format codecs
|
|
* and initialize the codecs. */
|
|
audio_st = NULL;
|
|
if (fmt->video_codec != AV_CODEC_ID_NONE) {
|
|
add_video_stream(&video_st, oc, fmt->video_codec);
|
|
have_video = 1;
|
|
}
|
|
if (fmt->audio_codec != AV_CODEC_ID_NONE) {
|
|
audio_st = add_audio_stream(oc, fmt->audio_codec);
|
|
}
|
|
|
|
/* Now that all the parameters are set, we can open the audio and
|
|
* video codecs and allocate the necessary encode buffers. */
|
|
if (have_video)
|
|
open_video(oc, &video_st);
|
|
if (audio_st)
|
|
open_audio(oc, audio_st);
|
|
|
|
av_dump_format(oc, 0, filename, 1);
|
|
|
|
/* open the output file, if needed */
|
|
if (!(fmt->flags & AVFMT_NOFILE)) {
|
|
if (avio_open(&oc->pb, filename, AVIO_FLAG_WRITE) < 0) {
|
|
fprintf(stderr, "Could not open '%s'\n", filename);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/* Write the stream header, if any. */
|
|
avformat_write_header(oc, NULL);
|
|
|
|
for (;;) {
|
|
/* Compute current audio and video time. */
|
|
if (audio_st)
|
|
audio_pts = (double)audio_st->pts.val * audio_st->time_base.num / audio_st->time_base.den;
|
|
else
|
|
audio_pts = 0.0;
|
|
|
|
if (have_video)
|
|
video_pts = (double)video_st.st->pts.val * video_st.st->time_base.num /
|
|
video_st.st->time_base.den;
|
|
else
|
|
video_pts = 0.0;
|
|
|
|
if ((!audio_st || audio_pts >= STREAM_DURATION) &&
|
|
(!have_video || video_pts >= STREAM_DURATION))
|
|
break;
|
|
|
|
/* write interleaved audio and video frames */
|
|
if (!have_video || (have_video && audio_st && audio_pts < video_pts)) {
|
|
write_audio_frame(oc, audio_st);
|
|
} else {
|
|
write_video_frame(oc, &video_st);
|
|
}
|
|
}
|
|
|
|
/* Write the trailer, if any. The trailer must be written before you
|
|
* close the CodecContexts open when you wrote the header; otherwise
|
|
* av_write_trailer() may try to use memory that was freed on
|
|
* av_codec_close(). */
|
|
av_write_trailer(oc);
|
|
|
|
/* Close each codec. */
|
|
if (have_video)
|
|
close_video(oc, &video_st);
|
|
if (audio_st)
|
|
close_audio(oc, audio_st);
|
|
|
|
/* Free the streams. */
|
|
for (i = 0; i < oc->nb_streams; i++) {
|
|
av_freep(&oc->streams[i]->codec);
|
|
av_freep(&oc->streams[i]);
|
|
}
|
|
|
|
if (!(fmt->flags & AVFMT_NOFILE))
|
|
/* Close the output file. */
|
|
avio_close(oc->pb);
|
|
|
|
/* free the stream */
|
|
av_free(oc);
|
|
|
|
return 0;
|
|
}
|