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.
#define MKTAG(a, b, c, d)
static int read_header(AVFormatContext *s)
static int probe(const AVProbeData *p)
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
static int read_packet(AVFormatContext *s, AVPacket *pkt)
int64_t duration
Decoding: duration of the stream, in stream time base.
unsigned int avio_rl16(AVIOContext *s)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
enum AVStreamParseType need_parsing
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Rational number (pair of numerator and denominator).
AVInputFormat ff_ivf_demuxer
This structure contains the data a format has to probe a file.
unsigned int avio_rl32(AVIOContext *s)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
const AVCodecTag ff_codec_bmp_tags[]
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
This structure stores compressed data.
int64_t pos
byte position in stream, -1 if unknown
uint64_t avio_rl64(AVIOContext *s)
#define AVERROR_INVALIDDATA
Invalid data found when processing input.