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
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
enum AVMediaType codec_type
General type of the encoded data.
This struct describes the properties of an encoded stream.
int buf_size
Size of buf except extra allocated bytes.
int nb_channels
Number of channels in this layout.
static int mtaf_read_header(AVFormatContext *s)
int64_t duration
Decoding: duration of the stream, in stream time base.
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
AVCodecParameters * codecpar
Codec parameters associated with this stream.
This structure contains the data a format has to probe a file.
AVChannelLayout ch_layout
Audio only.
int sample_rate
Audio only.
unsigned int avio_rl32(AVIOContext *s)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
const AVInputFormat ff_mtaf_demuxer
int avio_r8(AVIOContext *s)
int block_align
Audio only.
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
static int mtaf_read_packet(AVFormatContext *s, AVPacket *pkt)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
This structure stores compressed data.
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
static int mtaf_probe(const AVProbeData *p)
#define MKTAG(a, b, c, d)