46 #define STREAM_DURATION 10.0
47 #define STREAM_FRAME_RATE 25
48 #define STREAM_PIX_FMT AV_PIX_FMT_YUV420P
50 #define SCALE_FLAGS SWS_BICUBIC
74 printf(
"pts:%s pts_time:%s dts:%s dts_time:%s duration:%s duration_time:%s stream_index:%d\n",
89 fprintf(stderr,
"Error sending a frame to the encoder: %s\n",
101 fprintf(stderr,
"Error encoding a frame: %s\n",
av_err2str(ret));
114 fprintf(stderr,
"Error while writing output packet: %s\n",
av_err2str(ret));
133 fprintf(stderr,
"Could not find encoder for '%s'\n",
140 fprintf(stderr,
"Could not allocate stream\n");
146 fprintf(stderr,
"Could not alloc an encoding context\n");
151 switch ((*codec)->type) {
153 c->sample_fmt = (*codec)->sample_fmts ?
156 c->sample_rate = 44100;
157 if ((*codec)->supported_samplerates) {
158 c->sample_rate = (*codec)->supported_samplerates[0];
159 for (
i = 0; (*codec)->supported_samplerates[
i];
i++) {
160 if ((*codec)->supported_samplerates[
i] == 44100)
161 c->sample_rate = 44100;
166 if ((*codec)->channel_layouts) {
167 c->channel_layout = (*codec)->channel_layouts[0];
168 for (
i = 0; (*codec)->channel_layouts[
i];
i++) {
180 c->bit_rate = 400000;
218 uint64_t channel_layout,
225 fprintf(stderr,
"Error allocating an audio frame\n");
237 fprintf(stderr,
"Error allocating an audio buffer\n");
259 fprintf(stderr,
"Could not open audio codec: %s\n",
av_err2str(ret));
265 ost->tincr = 2 *
M_PI * 110.0 /
c->sample_rate;
267 ost->tincr2 = 2 *
M_PI * 110.0 /
c->sample_rate /
c->sample_rate;
272 nb_samples =
c->frame_size;
275 c->sample_rate, nb_samples);
277 c->sample_rate, nb_samples);
282 fprintf(stderr,
"Could not copy the stream parameters\n");
289 fprintf(stderr,
"Could not allocate resampler context\n");
303 fprintf(stderr,
"Failed to initialize the resampling context\n");
322 v = (
int)(sin(
ost->t) * 10000);
323 for (
i = 0;
i <
ost->enc->channels;
i++)
326 ost->tincr +=
ost->tincr2;
367 ost->frame->data, dst_nb_samples,
370 fprintf(stderr,
"Error while converting\n");
376 ost->samples_count += dst_nb_samples;
401 fprintf(stderr,
"Could not allocate frame data.\n");
420 fprintf(stderr,
"Could not open video codec: %s\n",
av_err2str(ret));
427 fprintf(stderr,
"Could not allocate video frame\n");
437 if (!
ost->tmp_frame) {
438 fprintf(stderr,
"Could not allocate temporary picture\n");
446 fprintf(stderr,
"Could not copy the stream parameters\n");
460 for (y = 0; y <
height; y++)
461 for (x = 0; x <
width; x++)
466 for (x = 0; x <
width / 2; x++) {
498 "Could not initialize the conversion context\n");
504 ost->tmp_frame->linesize, 0,
c->height,
ost->frame->data,
505 ost->frame->linesize);
510 ost->frame->pts =
ost->next_pts++;
536 int main(
int argc,
char **argv)
539 const char *filename;
542 AVCodec *audio_codec, *video_codec;
544 int have_video = 0, have_audio = 0;
545 int encode_video = 0, encode_audio = 0;
550 printf(
"usage: %s output_file\n"
551 "API example program to output a media file with libavformat.\n"
552 "This program generates a synthetic audio and video stream, encodes and\n"
553 "muxes them into a file named output_file.\n"
554 "The output format is automatically guessed according to the file extension.\n"
555 "Raw images can also be output by using '%%d' in the filename.\n"
561 for (
i = 2;
i+1 < argc;
i+=2) {
562 if (!strcmp(argv[
i],
"-flags") || !strcmp(argv[
i],
"-fflags"))
569 printf(
"Could not deduce output format from file extension: using MPEG.\n");
604 fprintf(stderr,
"Could not open '%s': %s\n", filename,
613 fprintf(stderr,
"Error occurred when opening output file: %s\n",
618 while (encode_video || encode_audio) {
simple assert() macros that are a bit more flexible than ISO C assert().
#define av_assert0(cond)
assert() equivalent, that is always enabled.
int avio_open(AVIOContext **s, const char *url, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
#define AVIO_FLAG_WRITE
write-only
int avio_closep(AVIOContext **s)
Close the resource accessed by the AVIOContext *s, free it and set the pointer pointing to it to NULL...
audio channel layout utility functions
static AVFormatContext * fmt_ctx
static enum AVPixelFormat pix_fmt
#define AV_CH_LAYOUT_STEREO
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
#define AV_CODEC_CAP_VARIABLE_FRAME_SIZE
Audio encoder supports receiving a different number of samples in each call.
#define AV_CODEC_FLAG_GLOBAL_HEADER
Place global headers in extradata instead of every keyframe.
AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
AVCodecID
Identify the syntax and semantics of the bitstream.
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
@ AV_CODEC_ID_MPEG2VIDEO
preferred ID for MPEG-1/2 video decoding
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
void av_packet_rescale_ts(AVPacket *pkt, AVRational src_tb, AVRational dst_tb)
Convert valid timing fields (timestamps / durations) in a packet from one timebase to another.
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
av_warn_unused_result int avformat_write_header(AVFormatContext *s, AVDictionary **options)
Allocate the stream private data and write the stream header to an output media file.
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output)
Print detailed information about the input or output format, such as duration, bitrate,...
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values.
int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
#define AVERROR_EOF
End of file.
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
int av_frame_get_buffer(AVFrame *frame, int align)
Allocate new buffer(s) for audio or video data.
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b)
Compare two timestamps each in its own time base.
int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd)
Rescale a 64-bit integer with specified rounding.
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
@ AV_ROUND_UP
Round toward +infinity.
AVSampleFormat
Audio sample formats.
@ AV_SAMPLE_FMT_FLTP
float, planar
@ AV_SAMPLE_FMT_S16
signed 16 bits
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
int attribute_align_arg sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[], const int srcStride[], int srcSliceY, int srcSliceH, uint8_t *const dst[], const int dstStride[])
swscale wrapper, so we don't need to export the SwsContext.
struct SwsContext * sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat, int dstW, int dstH, enum AVPixelFormat dstFormat, int flags, SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
Allocate and return an SwsContext.
int64_t swr_get_delay(struct SwrContext *s, int64_t base)
Gets the delay the next input sample will experience relative to the next output sample.
av_cold void swr_free(SwrContext **ss)
Free the given SwrContext and set the pointer to NULL.
av_cold int swr_init(struct SwrContext *s)
Initialize context after user parameters have been set.
av_cold struct SwrContext * swr_alloc(void)
Allocate SwrContext.
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
int av_opt_set_sample_fmt(void *obj, const char *name, enum AVSampleFormat fmt, int search_flags)
static int write_frame(AVFormatContext *fmt_ctx, AVCodecContext *c, AVStream *st, AVFrame *frame)
static AVFrame * alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
static AVFrame * get_video_frame(OutputStream *ost)
static void open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
static AVFrame * alloc_audio_frame(enum AVSampleFormat sample_fmt, uint64_t channel_layout, int sample_rate, int nb_samples)
int main(int argc, char **argv)
static int write_video_frame(AVFormatContext *oc, OutputStream *ost)
static AVFrame * get_audio_frame(OutputStream *ost)
static int write_audio_frame(AVFormatContext *oc, OutputStream *ost)
static void close_stream(AVFormatContext *oc, OutputStream *ost)
static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt)
static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
#define STREAM_FRAME_RATE
static void open_audio(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
static void add_stream(OutputStream *ost, AVFormatContext *oc, AVCodec **codec, enum AVCodecID codec_id)
AVPixelFormat
Pixel format.
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
main external API structure.
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
AVIOContext * pb
I/O context.
ff_const59 struct AVOutputFormat * oformat
The output container format.
AVStream ** streams
A list of all streams in the file.
This structure describes decoded (raw) audio or video data.
int nb_samples
number of audio samples (per channel) described by this frame
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
uint64_t channel_layout
Channel layout of the audio data.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
int sample_rate
Sample rate of the audio data.
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames,...
This structure stores compressed data.
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Rational number (pair of numerator and denominator).
AVCodecParameters * codecpar
Codec parameters associated with this stream.
int id
Format-specific stream ID.
int index
stream index in AVFormatContext
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
struct SwrContext * swr_ctx
struct SwsContext * sws_ctx
The libswresample context.
int attribute_align_arg swr_convert(struct SwrContext *s, uint8_t *out_arg[SWR_CH_MAX], int out_count, const uint8_t *in_arg[SWR_CH_MAX], int in_count)
libswresample public header
timestamp utils, mostly useful for debugging/logging purposes
#define av_ts2str(ts)
Convenience macro, the return value should be used only directly in function arguments but never stan...
#define av_ts2timestr(ts, tb)
Convenience macro, the return value should be used only directly in function arguments but never stan...