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+/*
+ * 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.
+ *
+ * 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/mathematics.h"
+#include "libavformat/avformat.h"
+#include "libswscale/swscale.h"
+
+#undef exit
+
+/* 5 seconds stream duration */
+#define STREAM_DURATION 200.0
+#define STREAM_FRAME_RATE 25 /* 25 images/s */
+#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * STREAM_FRAME_RATE))
+#define STREAM_PIX_FMT PIX_FMT_YUV420P /* default pix_fmt */
+
+static int sws_flags = SWS_BICUBIC;
+
+/**************************************************************/
+/* audio output */
+
+static float t, tincr, tincr2;
+static int16_t *samples;
+static uint8_t *audio_outbuf;
+static int audio_outbuf_size;
+static int audio_input_frame_size;
+
+/*
+ * add an audio output stream
+ */
+static AVStream *add_audio_stream(AVFormatContext *oc, enum CodecID codec_id)
+{
+ AVCodecContext *c;
+ AVStream *st;
+
+ st = avformat_new_stream(oc, NULL);
+ if (!st) {
+ fprintf(stderr, "Could not alloc stream\n");
+ exit(1);
+ }
+ st->id = 1;
+
+ c = st->codec;
+ c->codec_id = codec_id;
+ c->codec_type = AVMEDIA_TYPE_AUDIO;
+
+ /* put sample parameters */
+ c->sample_fmt = AV_SAMPLE_FMT_S16;
+ c->bit_rate = 64000;
+ c->sample_rate = 44100;
+ c->channels = 2;
+
+ // 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;
+ AVCodec *codec;
+
+ c = st->codec;
+
+ /* find the audio encoder */
+ codec = avcodec_find_encoder(c->codec_id);
+ if (!codec) {
+ fprintf(stderr, "codec not found\n");
+ exit(1);
+ }
+
+ /* open it */
+ if (avcodec_open(c, codec) < 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;
+
+ audio_outbuf_size = 10000;
+ audio_outbuf = av_malloc(audio_outbuf_size);
+
+ /* ugly hack for PCM codecs (will be removed ASAP with new PCM
+ support to compute the input frame size in samples */
+ if (c->frame_size <= 1) {
+ audio_input_frame_size = audio_outbuf_size / c->channels;
+ switch(st->codec->codec_id) {
+ case CODEC_ID_PCM_S16LE:
+ case CODEC_ID_PCM_S16BE:
+ case CODEC_ID_PCM_U16LE:
+ case CODEC_ID_PCM_U16BE:
+ audio_input_frame_size >>= 1;
+ break;
+ default:
+ break;
+ }
+ } else {
+ audio_input_frame_size = c->frame_size;
+ }
+ samples = av_malloc(audio_input_frame_size * 2 * 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;
+ av_init_packet(&pkt);
+
+ c = st->codec;
+
+ get_audio_frame(samples, audio_input_frame_size, c->channels);
+
+ pkt.size = avcodec_encode_audio(c, audio_outbuf, audio_outbuf_size, samples);
+
+ if (c->coded_frame && c->coded_frame->pts != AV_NOPTS_VALUE)
+ pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
+ pkt.flags |= AV_PKT_FLAG_KEY;
+ pkt.stream_index = st->index;
+ pkt.data = audio_outbuf;
+
+ /* write the compressed frame in the media file */
+ if (av_interleaved_write_frame(oc, &pkt) != 0) {
+ fprintf(stderr, "Error while writing audio frame\n");
+ exit(1);
+ }
+}
+
+static void close_audio(AVFormatContext *oc, AVStream *st)
+{
+ avcodec_close(st->codec);
+
+ av_free(samples);
+ av_free(audio_outbuf);
+}
+
+/**************************************************************/
+/* video output */
+
+static AVFrame *picture, *tmp_picture;
+static uint8_t *video_outbuf;
+static int frame_count, video_outbuf_size;
+
+/* add a video output stream */
+static AVStream *add_video_stream(AVFormatContext *oc, enum CodecID codec_id)
+{
+ AVCodecContext *c;
+ AVStream *st;
+ AVCodec *codec;
+
+ st = avformat_new_stream(oc, NULL);
+ if (!st) {
+ fprintf(stderr, "Could not alloc stream\n");
+ exit(1);
+ }
+
+ c = st->codec;
+
+ /* find the video encoder */
+ codec = avcodec_find_encoder(codec_id);
+ if (!codec) {
+ fprintf(stderr, "codec not found\n");
+ exit(1);
+ }
+ avcodec_get_context_defaults3(c, codec);
+
+ c->codec_id = codec_id;
+
+ /* put sample parameters */
+ c->bit_rate = 400000;
+ /* resolution must be a multiple of two */
+ c->width = 352;
+ c->height = 288;
+ /* time base: 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
+ identically 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 == CODEC_ID_MPEG2VIDEO) {
+ /* just for testing, we also add B frames */
+ c->max_b_frames = 2;
+ }
+ if (c->codec_id == 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;
+
+ return st;
+}
+
+static AVFrame *alloc_picture(enum PixelFormat pix_fmt, int width, int height)
+{
+ AVFrame *picture;
+ uint8_t *picture_buf;
+ int size;
+
+ picture = avcodec_alloc_frame();
+ if (!picture)
+ return NULL;
+ size = avpicture_get_size(pix_fmt, width, height);
+ picture_buf = av_malloc(size);
+ if (!picture_buf) {
+ av_free(picture);
+ return NULL;
+ }
+ avpicture_fill((AVPicture *)picture, picture_buf,
+ pix_fmt, width, height);
+ return picture;
+}
+
+static void open_video(AVFormatContext *oc, AVStream *st)
+{
+ AVCodec *codec;
+ AVCodecContext *c;
+
+ c = st->codec;
+
+ /* find the video encoder */
+ codec = avcodec_find_encoder(c->codec_id);
+ if (!codec) {
+ fprintf(stderr, "codec not found\n");
+ exit(1);
+ }
+
+ /* open the codec */
+ if (avcodec_open(c, codec) < 0) {
+ fprintf(stderr, "could not open codec\n");
+ exit(1);
+ }
+
+ video_outbuf = NULL;
+ if (!(oc->oformat->flags & AVFMT_RAWPICTURE)) {
+ /* allocate output buffer */
+ /* XXX: API change will be done */
+ /* buffers passed into lav* can be allocated any way you prefer,
+ as long as they're aligned enough for the architecture, and
+ they're freed appropriately (such as using av_free for buffers
+ allocated with av_malloc) */
+ video_outbuf_size = 200000;
+ video_outbuf = av_malloc(video_outbuf_size);
+ }
+
+ /* allocate the encoded raw picture */
+ picture = alloc_picture(c->pix_fmt, c->width, c->height);
+ if (!picture) {
+ 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 */
+ tmp_picture = NULL;
+ if (c->pix_fmt != PIX_FMT_YUV420P) {
+ tmp_picture = alloc_picture(PIX_FMT_YUV420P, c->width, c->height);
+ if (!tmp_picture) {
+ 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;
+
+ 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, AVStream *st)
+{
+ int out_size, ret;
+ AVCodecContext *c;
+ static struct SwsContext *img_convert_ctx;
+
+ c = st->codec;
+
+ if (frame_count >= STREAM_NB_FRAMES) {
+ /* no more frame 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 != 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,
+ 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(tmp_picture, frame_count, c->width, c->height);
+ sws_scale(img_convert_ctx, tmp_picture->data, tmp_picture->linesize,
+ 0, c->height, picture->data, picture->linesize);
+ } else {
+ fill_yuv_image(picture, 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 = st->index;
+ pkt.data = (uint8_t *)picture;
+ pkt.size = sizeof(AVPicture);
+
+ ret = av_interleaved_write_frame(oc, &pkt);
+ } else {
+ /* encode the image */
+ out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
+ /* if zero size, it means the image was buffered */
+ if (out_size > 0) {
+ AVPacket pkt;
+ av_init_packet(&pkt);
+
+ if (c->coded_frame->pts != AV_NOPTS_VALUE)
+ pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
+ if(c->coded_frame->key_frame)
+ pkt.flags |= AV_PKT_FLAG_KEY;
+ pkt.stream_index = st->index;
+ pkt.data = video_outbuf;
+ pkt.size = out_size;
+
+ /* write the compressed frame in 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, AVStream *st)
+{
+ avcodec_close(st->codec);
+ av_free(picture->data[0]);
+ av_free(picture);
+ if (tmp_picture) {
+ av_free(tmp_picture->data[0]);
+ av_free(tmp_picture);
+ }
+ av_free(video_outbuf);
+}
+
+/**************************************************************/
+/* media file output */
+
+int main(int argc, char **argv)
+{
+ const char *filename;
+ AVOutputFormat *fmt;
+ AVFormatContext *oc;
+ AVStream *audio_st, *video_st;
+ double audio_pts, video_pts;
+ 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];
+
+ /* allocate the output media context */
+ avformat_alloc_output_context2(&oc, NULL, NULL, filename);
+ if (!oc) {
+ printf("Could not deduce output format from file extension: using MPEG.\n");
+ avformat_alloc_output_context2(&oc, NULL, "mpeg", filename);
+ }
+ if (!oc) {
+ return 1;
+ }
+ fmt = oc->oformat;
+
+ /* add the audio and video streams using the default format codecs
+ and initialize the codecs */
+ video_st = NULL;
+ audio_st = NULL;
+ if (fmt->video_codec != CODEC_ID_NONE) {
+ video_st = add_video_stream(oc, fmt->video_codec);
+ }
+ if (fmt->audio_codec != CODEC_ID_NONE) {
+ audio_st = add_audio_stream(oc, fmt->audio_codec);
+ }
+
+ av_dump_format(oc, 0, filename, 1);
+
+ /* now that all the parameters are set, we can open the audio and
+ video codecs and allocate the necessary encode buffers */
+ if (video_st)
+ open_video(oc, video_st);
+ if (audio_st)
+ open_audio(oc, audio_st);
+
+ /* 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);
+ picture->pts = 0;
+ 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 (video_st)
+ video_pts = (double)video_st->pts.val * video_st->time_base.num / video_st->time_base.den;
+ else
+ video_pts = 0.0;
+
+ if ((!audio_st || audio_pts >= STREAM_DURATION) &&
+ (!video_st || video_pts >= STREAM_DURATION))
+ break;
+
+ /* write interleaved audio and video frames */
+ if (!video_st || (video_st && audio_st && audio_pts < video_pts)) {
+ write_audio_frame(oc, audio_st);
+ } else {
+ write_video_frame(oc, video_st);
+ picture->pts++;
+ }
+ }
+
+ /* write the trailer, if any. the trailer must be written
+ * before you close the CodecContexts open when you wrote the
+ * header; otherwise write_trailer may try to use memory that
+ * was freed on av_codec_close() */
+ av_write_trailer(oc);
+
+ /* close each codec */
+ if (video_st)
+ 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;
+}
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