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 struct describes the properties of an encoded stream.
static int ircam_write_header(AVFormatContext *s)
int nb_channels
Number of channels in this layout.
uint32_t av_q2intfloat(AVRational q)
Convert an AVRational to a IEEE 32-bit float expressed in fixed-point format.
const FFOutputFormat ff_ircam_muxer
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
const AVCodecTag ff_codec_ircam_le_tags[]
Rational number (pair of numerator and denominator).
void ffio_fill(AVIOContext *s, int b, int64_t count)
AVChannelLayout ch_layout
Audio only.
int sample_rate
Audio only.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
void avio_wl32(AVIOContext *s, unsigned int val)
#define FF_OFMT_FLAG_MAX_ONE_OF_EACH
If this flag is set, it indicates that for each codec type whose corresponding default codec (i....
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).