40 #include <alsa/asoundlib.h> 66 res =
ff_alsa_open(s1, SND_PCM_STREAM_PLAYBACK, &sample_rate,
70 "sample rate %d not available, nearest is %d\n",
102 while ((res = snd_pcm_writei(s->
h, buf, size)) < 0) {
103 if (res == -EAGAIN) {
130 pkt.
data = (*frame)->data[0];
132 pkt.
dts = (*frame)->pkt_dts;
133 pkt.
duration = (*frame)->pkt_duration;
139 int64_t *dts, int64_t *wall)
142 snd_pcm_sframes_t delay = 0;
144 snd_pcm_delay(s->
h, &delay);
173 .priv_class = &alsa_muxer_class,
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
This structure describes decoded (raw) audio or video data.
#define LIBAVUTIL_VERSION_INT
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
const char * av_default_item_name(void *ptr)
Return the context name.
int64_t timestamp
current timestamp, without latency applied.
AVOutputFormat ff_alsa_muxer
ALSA input and output: definitions and structures.
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
AVStream ** streams
A list of all streams in the file.
static av_cold int audio_write_header(AVFormatContext *s1)
static int audio_write_frame(AVFormatContext *s1, int stream_index, AVFrame **frame, unsigned flags)
int ff_alsa_extend_reorder_buf(AlsaData *s, int min_size)
int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt)
Check if the sample format is planar.
Main libavdevice API header.
AVCodecID
Identify the syntax and semantics of the bitstream.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
static int audio_write_packet(AVFormatContext *s1, AVPacket *pkt)
enum AVMediaType codec_type
General type of the encoded data.
common internal API header
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
void(* reorder_func)(const void *, void *, int)
static int write_trailer(AVFormatContext *s1)
static const AVClass alsa_muxer_class
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
int64_t av_gettime(void)
Get the current time in microseconds.
int ff_alsa_xrun_recover(AVFormatContext *s1, int err)
Try to recover from ALSA buffer underrun.
av_cold int ff_alsa_close(AVFormatContext *s1)
Close the ALSA PCM.
static int audio_get_device_list(AVFormatContext *h, AVDeviceInfoList *device_list)
static void audio_get_output_timestamp(AVFormatContext *s1, int stream, int64_t *dts, int64_t *wall)
Describe the class of an AVClass context structure.
int ff_alsa_get_device_list(AVDeviceInfoList *device_list, snd_pcm_stream_t stream_type)
#define flags(name, subs,...)
int sample_rate
Audio only.
void * priv_data
Format private data.
static void write_header(FFV1Context *f)
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
int frame_size
bytes per sample * channels
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
int reorder_buf_size
in frames
#define AV_NOPTS_VALUE
Undefined timestamp value.
av_cold int ff_alsa_open(AVFormatContext *ctx, snd_pcm_stream_t mode, unsigned int *sample_rate, int channels, enum AVCodecID *codec_id)
Open an ALSA PCM.