52 #define DURATION_LONGEST 0 53 #define DURATION_SHORTEST 1 54 #define DURATION_FIRST 2 81 while (frame_list->
list) {
94 if (!frame_list->
list)
101 if (!frame_list->
list)
112 while (samples > 0) {
118 if (!frame_list->
list)
142 if (!frame_list->
list) {
181 #define OFFSET(x) offsetof(MixContext, x) 182 #define A AV_OPT_FLAG_AUDIO_PARAM 183 #define F AV_OPT_FLAG_FILTERING_PARAM 184 #define T AV_OPT_FLAG_RUNTIME_PARAM 186 {
"inputs",
"Number of inputs.",
188 {
"duration",
"How to determine the end-of-stream.",
193 {
"dropout_transition",
"Transition time, in seconds, for volume " 194 "renormalization when an input stream ends.",
196 {
"weights",
"Set weight for each input.",
212 float weight_sum = 0.f;
281 "inputs:%d fmt:%s srate:%d cl:%s\n", s->
nb_inputs,
303 if (ns < nb_samples) {
316 nb_samples = INT_MAX;
320 nb_samples =
FFMIN(nb_samples, ns);
323 if (nb_samples == INT_MAX) {
348 int planes, plane_size, p;
355 plane_size =
FFALIGN(plane_size, 16);
359 for (p = 0; p <
planes; p++) {
365 for (p = 0; p <
planes; p++) {
412 int active_inputs = 0;
417 if (!active_inputs ||
512 float last_weight = 1.f;
607 char *res,
int res_len,
int flags)
637 .priv_class = &amix_class,
643 .
outputs = avfilter_af_amix_outputs,
int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe)
Take a frame from the link's FIFO and update the link's stats.
AVAudioFifo * av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels, int nb_samples)
Allocate an AVAudioFifo.
int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples)
Read data from an AVAudioFifo.
This structure describes decoded (raw) audio or video data.
#define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter)
Forward the status on an output link to all input links.
Main libavfilter public API header.
static av_cold void uninit(AVFilterContext *ctx)
void av_audio_fifo_free(AVAudioFifo *af)
Free an AVAudioFifo.
#define AVFILTER_FLAG_DYNAMIC_INPUTS
The number of the filter inputs is not determined just by AVFilter.inputs.
static const struct @319 planes[]
enum AVMediaType type
AVFilterPad type.
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
static int frame_list_next_frame_size(FrameList *frame_list)
static void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the source filter.
void ff_inlink_request_frame(AVFilterLink *link)
Mark that a frame is wanted on the link.
Macro definitions for various function/variable attributes.
Linked list used to store timestamps and frame sizes of all frames in the FIFO for the first input...
const char * name
Pad name.
AVFilterLink ** inputs
array of pointers to input links
#define av_assert0(cond)
assert() equivalent, that is always enabled.
void(* vector_fmac_scalar)(float *dst, const float *src, float mul, int len)
Multiply a vector of floats by a scalar float and add to destination vector.
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
static int activate(AVFilterContext *ctx)
static int64_t frame_list_next_pts(FrameList *frame_list)
static int request_samples(AVFilterContext *ctx, int min_samples)
Requests a frame, if needed, from each input link other than the first.
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
static const AVFilterPad avfilter_af_amix_outputs[]
static int calc_active_inputs(MixContext *s)
Calculates the number of active inputs and determines EOF based on the duration option.
int sample_rate
sample rate
static int query_formats(AVFilterContext *ctx)
#define AVERROR_EOF
End of file.
#define AV_LOG_VERBOSE
Detailed information.
float dropout_transition
transition time when an input drops out
FrameList * frame_list
list of frame info for the first input
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the ff_outlink_frame_wanted() function.If this function returns true
float * input_scale
mixing scale factor for each input
int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt)
Check if the sample format is planar.
A filter pad used for either input or output.
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
A link between two filters.
int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts)
Test and acknowledge the change of status on the link.
AVAudioFifo ** fifos
audio fifo for each input
void(* vector_dmac_scalar)(double *dst, const double *src, double mul, int len)
Multiply a vector of doubles by a scalar double and add to destination vector.
AVFilterPad * input_pads
array of input pads
av_cold AVFloatDSPContext * avpriv_float_dsp_alloc(int bit_exact)
Allocate a float DSP context.
int sample_rate
samples per second
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options...
void * priv
private data for use by the filter
AVRational time_base
Define the time base used by the PTS of the frames/samples which will pass through this link...
simple assert() macros that are a bit more flexible than ISO C assert().
static void parse_weights(AVFilterContext *ctx)
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Context for an Audio FIFO Buffer.
char * av_asprintf(const char *fmt,...)
int active_inputs
number of input currently active
int av_audio_fifo_size(AVAudioFifo *af)
Get the current number of samples in the AVAudioFifo available for reading.
audio channel layout utility functions
unsigned nb_inputs
number of input pads
static void frame_list_remove_samples(FrameList *frame_list, int nb_samples)
int duration_mode
mode for determining duration
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
AVFilterContext * src
source filter
float weight_sum
sum of custom weights for every input
int nb_channels
number of channels
static const AVFilterPad outputs[]
int format
agreed upon media format
static int frame_list_add_frame(FrameList *frame_list, int nb_samples, int64_t pts)
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.
double av_strtod(const char *numstr, char **tail)
Parse the string in numstr and return its value as a double.
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
AVSampleFormat
Audio sample formats.
uint8_t * input_state
current state of each input
float * scale_norm
normalization factor for every input
char * weights_str
string for custom weights for every input
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 inputs
Describe the class of an AVClass context structure.
Rational number (pair of numerator and denominator).
they must not be accessed directly The fifo field contains the frames that are queued in the input for processing by the filter The status_in and status_out fields contains the queued status(EOF or error) of the link
const char * name
Filter name.
static int output_frame(AVFilterLink *outlink)
Read samples from the input FIFOs, mix, and write to the output link.
#define INPUT_ON
input is active
AVFilterLink ** outputs
array of pointers to output links
int64_t next_pts
calculated pts for next output frame
#define DURATION_SHORTEST
#define flags(name, subs,...)
int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples)
Write data to an AVAudioFifo.
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
#define ns(max_value, name, subs,...)
#define INPUT_EOF
input has reached EOF (may still be active)
static void calculate_scales(MixContext *s, int nb_samples)
Update the scaling factors to apply to each input during mixing.
common internal and external API header
AVFILTER_DEFINE_CLASS(amix)
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
uint64_t channel_layout
channel layout of current buffer (see libavutil/channel_layout.h)
int channels
Number of channels.
static const AVOption amix_options[]
float * weights
custom weights for every input
int nb_inputs
number of inputs
static enum AVSampleFormat sample_fmts[]
Filter the word “frame” indicates either a video frame or a group of audio samples
static av_cold int init(AVFilterContext *ctx)
static int config_output(AVFilterLink *outlink)
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
uint8_t ** extended_data
pointers to the data planes/channels.
int nb_samples
number of audio samples (per channel) described by this frame
static void frame_list_clear(FrameList *frame_list)
#define AV_NOPTS_VALUE
Undefined timestamp value.
simple arithmetic expression evaluator
void * av_mallocz_array(size_t nmemb, size_t size)
static int ff_insert_inpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new input pad for the filter.