ffmpeg/libavfilter/filters.h

607 lines
21 KiB
C

/*
* Filters implementation helper functions
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVFILTER_FILTERS_H
#define AVFILTER_FILTERS_H
/**
* Filters implementation helper functions
*/
#include "avfilter.h"
/**
* Special return code when activate() did not do anything.
*/
#define FFERROR_NOT_READY FFERRTAG('N','R','D','Y')
/**
* A filter pad used for either input or output.
*/
struct AVFilterPad {
/**
* Pad name. The name is unique among inputs and among outputs, but an
* input may have the same name as an output. This may be NULL if this
* pad has no need to ever be referenced by name.
*/
const char *name;
/**
* AVFilterPad type.
*/
enum AVMediaType type;
/**
* The filter expects writable frames from its input link,
* duplicating data buffers if needed.
*
* input pads only.
*/
#define AVFILTERPAD_FLAG_NEEDS_WRITABLE (1 << 0)
/**
* The pad's name is allocated and should be freed generically.
*/
#define AVFILTERPAD_FLAG_FREE_NAME (1 << 1)
/**
* A combination of AVFILTERPAD_FLAG_* flags.
*/
int flags;
/**
* Callback functions to get a video/audio buffers. If NULL,
* the filter system will use ff_default_get_video_buffer() for video
* and ff_default_get_audio_buffer() for audio.
*
* The state of the union is determined by type.
*
* Input pads only.
*/
union {
AVFrame *(*video)(AVFilterLink *link, int w, int h);
AVFrame *(*audio)(AVFilterLink *link, int nb_samples);
} get_buffer;
/**
* Filtering callback. This is where a filter receives a frame with
* audio/video data and should do its processing.
*
* Input pads only.
*
* @return >= 0 on success, a negative AVERROR on error. This function
* must ensure that frame is properly unreferenced on error if it
* hasn't been passed on to another filter.
*/
int (*filter_frame)(AVFilterLink *link, AVFrame *frame);
/**
* Frame request callback. A call to this should result in some progress
* towards producing output over the given link. This should return zero
* on success, and another value on error.
*
* Output pads only.
*/
int (*request_frame)(AVFilterLink *link);
/**
* Link configuration callback.
*
* For output pads, this should set the link properties such as
* width/height. This should NOT set the format property - that is
* negotiated between filters by the filter system using the
* query_formats() callback before this function is called.
*
* For input pads, this should check the properties of the link, and update
* the filter's internal state as necessary.
*
* For both input and output filters, this should return zero on success,
* and another value on error.
*/
int (*config_props)(AVFilterLink *link);
};
/**
* Link properties exposed to filter code, but not external callers.
*
* Cf. AVFilterLink for public properties, FilterLinkInternal for
* properties private to the generic layer.
*/
typedef struct FilterLink {
AVFilterLink pub;
/**
* Graph the filter belongs to.
*/
struct AVFilterGraph *graph;
/**
* Current timestamp of the link, as defined by the most recent
* frame(s), in link time_base units.
*/
int64_t current_pts;
/**
* Current timestamp of the link, as defined by the most recent
* frame(s), in AV_TIME_BASE units.
*/
int64_t current_pts_us;
/**
* Minimum number of samples to filter at once.
*
* May be set by the link destination filter in its config_props().
* If 0, all related fields are ignored.
*/
int min_samples;
/**
* Maximum number of samples to filter at once. If filter_frame() is
* called with more samples, it will split them.
*
* May be set by the link destination filter in its config_props().
*/
int max_samples;
/**
* Number of past frames sent through the link.
*/
int64_t frame_count_in, frame_count_out;
/**
* Number of past samples sent through the link.
*/
int64_t sample_count_in, sample_count_out;
/**
* Frame rate of the stream on the link, or 1/0 if unknown or variable.
*
* May be set by the link source filter in its config_props(); if left to
* 0/0, will be automatically copied from the first input of the source
* filter if it exists.
*
* Sources should set it to the best estimation of the real frame rate.
* If the source frame rate is unknown or variable, set this to 1/0.
* Filters should update it if necessary depending on their function.
* Sinks can use it to set a default output frame rate.
* It is similar to the r_frame_rate field in AVStream.
*/
AVRational frame_rate;
/**
* For hwaccel pixel formats, this should be a reference to the
* AVHWFramesContext describing the frames.
*
* May be set by the link source filter in its config_props().
*/
AVBufferRef *hw_frames_ctx;
} FilterLink;
static inline FilterLink* ff_filter_link(AVFilterLink *link)
{
return (FilterLink*)link;
}
/**
* The filter is aware of hardware frames, and any hardware frame context
* should not be automatically propagated through it.
*/
#define FF_FILTER_FLAG_HWFRAME_AWARE (1 << 0)
/**
* Find the index of a link.
*
* I.e. find i such that link == ctx->(in|out)puts[i]
*/
#define FF_INLINK_IDX(link) ((int)((link)->dstpad - (link)->dst->input_pads))
#define FF_OUTLINK_IDX(link) ((int)((link)->srcpad - (link)->src->output_pads))
enum FilterFormatsState {
/**
* The default value meaning that this filter supports all formats
* and (for audio) sample rates and channel layouts/counts as long
* as these properties agree for all inputs and outputs.
* This state is only allowed in case all inputs and outputs actually
* have the same type.
* The union is unused in this state.
*
* This value must always be zero (for default static initialization).
*/
FF_FILTER_FORMATS_PASSTHROUGH = 0,
FF_FILTER_FORMATS_QUERY_FUNC, ///< formats.query active.
FF_FILTER_FORMATS_QUERY_FUNC2, ///< formats.query_func2 active.
FF_FILTER_FORMATS_PIXFMT_LIST, ///< formats.pixels_list active.
FF_FILTER_FORMATS_SAMPLEFMTS_LIST, ///< formats.samples_list active.
FF_FILTER_FORMATS_SINGLE_PIXFMT, ///< formats.pix_fmt active
FF_FILTER_FORMATS_SINGLE_SAMPLEFMT, ///< formats.sample_fmt active.
};
#define FILTER_QUERY_FUNC(func) \
.formats.query_func = func, \
.formats_state = FF_FILTER_FORMATS_QUERY_FUNC
#define FILTER_QUERY_FUNC2(func) \
.formats.query_func2 = func, \
.formats_state = FF_FILTER_FORMATS_QUERY_FUNC2
#define FILTER_PIXFMTS_ARRAY(array) \
.formats.pixels_list = array, \
.formats_state = FF_FILTER_FORMATS_PIXFMT_LIST
#define FILTER_SAMPLEFMTS_ARRAY(array) \
.formats.samples_list = array, \
.formats_state = FF_FILTER_FORMATS_SAMPLEFMTS_LIST
#define FILTER_PIXFMTS(...) \
FILTER_PIXFMTS_ARRAY(((const enum AVPixelFormat []) { __VA_ARGS__, AV_PIX_FMT_NONE }))
#define FILTER_SAMPLEFMTS(...) \
FILTER_SAMPLEFMTS_ARRAY(((const enum AVSampleFormat[]) { __VA_ARGS__, AV_SAMPLE_FMT_NONE }))
#define FILTER_SINGLE_PIXFMT(pix_fmt_) \
.formats.pix_fmt = pix_fmt_, \
.formats_state = FF_FILTER_FORMATS_SINGLE_PIXFMT
#define FILTER_SINGLE_SAMPLEFMT(sample_fmt_) \
.formats.sample_fmt = sample_fmt_, \
.formats_state = FF_FILTER_FORMATS_SINGLE_SAMPLEFMT
#define FILTER_INOUTPADS(inout, array) \
.inout = array, \
.nb_ ## inout = FF_ARRAY_ELEMS(array)
#define FILTER_INPUTS(array) FILTER_INOUTPADS(inputs, (array))
#define FILTER_OUTPUTS(array) FILTER_INOUTPADS(outputs, (array))
#define AVFILTER_DEFINE_CLASS_EXT(name, desc, options) \
static const AVClass name##_class = { \
.class_name = desc, \
.item_name = av_default_item_name, \
.option = options, \
.version = LIBAVUTIL_VERSION_INT, \
.category = AV_CLASS_CATEGORY_FILTER, \
}
#define AVFILTER_DEFINE_CLASS(fname) \
AVFILTER_DEFINE_CLASS_EXT(fname, #fname, fname##_options)
#define D2TS(d) (isnan(d) ? AV_NOPTS_VALUE : (int64_t)(d))
#define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
#define TS2T(ts, tb) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts) * av_q2d(tb))
/**
* Mark a filter ready and schedule it for activation.
*
* This is automatically done when something happens to the filter (queued
* frame, status change, request on output).
* Filters implementing the activate callback can call it directly to
* perform one more round of processing later.
* It is also useful for filters reacting to external or asynchronous
* events.
*/
void ff_filter_set_ready(AVFilterContext *filter, unsigned priority);
/**
* Get the number of frames available on the link.
* @return the number of frames available in the link fifo.
*/
size_t ff_inlink_queued_frames(AVFilterLink *link);
/**
* Test if a frame is available on the link.
* @return >0 if a frame is available
*/
int ff_inlink_check_available_frame(AVFilterLink *link);
/***
* Get the number of samples available on the link.
* @return the numer of samples available on the link.
*/
int ff_inlink_queued_samples(AVFilterLink *link);
/**
* Test if enough samples are available on the link.
* @return >0 if enough samples are available
* @note on EOF and error, min becomes 1
*/
int ff_inlink_check_available_samples(AVFilterLink *link, unsigned min);
/**
* Take a frame from the link's FIFO and update the link's stats.
*
* If ff_inlink_check_available_frame() was previously called, the
* preferred way of expressing it is "av_assert1(ret);" immediately after
* ff_inlink_consume_frame(). Negative error codes must still be checked.
*
* @note May trigger process_command() and/or update is_disabled.
* @return >0 if a frame is available,
* 0 and set rframe to NULL if no frame available,
* or AVERROR code
*/
int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe);
/**
* Take samples from the link's FIFO and update the link's stats.
*
* If ff_inlink_check_available_samples() was previously called, the
* preferred way of expressing it is "av_assert1(ret);" immediately after
* ff_inlink_consume_samples(). Negative error codes must still be checked.
*
* @note May trigger process_command() and/or update is_disabled.
* @return >0 if a frame is available,
* 0 and set rframe to NULL if no frame available,
* or AVERROR code
*/
int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max,
AVFrame **rframe);
/**
* Access a frame in the link fifo without consuming it.
* The first frame is numbered 0; the designated frame must exist.
* @return the frame at idx position in the link fifo.
*/
AVFrame *ff_inlink_peek_frame(AVFilterLink *link, size_t idx);
/**
* Make sure a frame is writable.
* This is similar to av_frame_make_writable() except it uses the link's
* buffer allocation callback, and therefore allows direct rendering.
*/
int ff_inlink_make_frame_writable(AVFilterLink *link, AVFrame **rframe);
/**
* Test and acknowledge the change of status on the link.
*
* Status means EOF or an error condition; a change from the normal (0)
* status to a non-zero status can be queued in a filter's input link, it
* becomes relevant after the frames queued in the link's FIFO are
* processed. This function tests if frames are still queued and if a queued
* status change has not yet been processed. In that case it performs basic
* treatment (updating the link's timestamp) and returns a positive value to
* let the filter do its own treatments (flushing...).
*
* Filters implementing the activate callback should call this function when
* they think it might succeed (usually after checking unsuccessfully for a
* queued frame).
* Filters implementing the filter_frame and request_frame callbacks do not
* need to call that since the same treatment happens in ff_filter_frame().
*
* @param[out] rstatus new or current status
* @param[out] rpts current timestamp of the link in link time base
* @return >0 if status changed, <0 if status already acked, 0 otherwise
*/
int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts);
/**
* Mark that a frame is wanted on the link.
* Unlike ff_filter_frame(), it must not be called when the link has a
* non-zero status, and thus does not acknowledge it.
* Also it cannot fail.
*/
void ff_inlink_request_frame(AVFilterLink *link);
/**
* Set the status on an input link.
* Also discard all frames in the link's FIFO.
*/
void ff_inlink_set_status(AVFilterLink *link, int status);
/**
* Test if a frame is wanted on an output link.
*/
int ff_outlink_frame_wanted(AVFilterLink *link);
/**
* Get the status on an output link.
*/
int ff_outlink_get_status(AVFilterLink *link);
/**
* Set the status field of a link from the source filter.
* The pts should reflect the timestamp of the status change,
* in link time base and relative to the frames timeline.
* In particular, for AVERROR_EOF, it should reflect the
* end time of the last frame.
*/
void ff_avfilter_link_set_in_status(AVFilterLink *link, int status, int64_t pts);
/**
* Set the status field of a link from the source filter.
* The pts should reflect the timestamp of the status change,
* in link time base and relative to the frames timeline.
* In particular, for AVERROR_EOF, it should reflect the
* end time of the last frame.
*/
static inline void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
{
ff_avfilter_link_set_in_status(link, status, pts);
}
/**
* Forward the status on an output link to an input link.
* If the status is set, it will discard all queued frames and this macro
* will return immediately.
*/
#define FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink) do { \
int ret = ff_outlink_get_status(outlink); \
if (ret) { \
ff_inlink_set_status(inlink, ret); \
return 0; \
} \
} while (0)
/**
* Forward the status on an output link to all input links.
* If the status is set, it will discard all queued frames and this macro
* will return immediately.
*/
#define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter) do { \
int ret = ff_outlink_get_status(outlink); \
if (ret) { \
unsigned i; \
for (i = 0; i < filter->nb_inputs; i++) \
ff_inlink_set_status(filter->inputs[i], ret); \
return 0; \
} \
} while (0)
/**
* Acknowledge the status on an input link and forward it to an output link.
* If the status is set, this macro will return immediately.
*/
#define FF_FILTER_FORWARD_STATUS(inlink, outlink) do { \
int status; \
int64_t pts; \
if (ff_inlink_acknowledge_status(inlink, &status, &pts)) { \
ff_outlink_set_status(outlink, status, pts); \
return 0; \
} \
} while (0)
/**
* Acknowledge the status on an input link and forward it to an output link.
* If the status is set, this macro will return immediately.
*/
#define FF_FILTER_FORWARD_STATUS_ALL(inlink, filter) do { \
int status; \
int64_t pts; \
if (ff_inlink_acknowledge_status(inlink, &status, &pts)) { \
unsigned i; \
for (i = 0; i < filter->nb_outputs; i++) \
ff_outlink_set_status(filter->outputs[i], status, pts); \
return 0; \
} \
} while (0)
/**
* Forward the frame_wanted_out flag from an output link to an input link.
* If the flag is set, this macro will return immediately.
*/
#define FF_FILTER_FORWARD_WANTED(outlink, inlink) do { \
if (ff_outlink_frame_wanted(outlink)) { \
ff_inlink_request_frame(inlink); \
return 0; \
} \
} while (0)
/**
* Check for flow control between input and output.
* This is necessary for filters that may produce several output frames for
* a single input event, otherwise they may produce them all at once,
* causing excessive memory consumption.
*/
int ff_inoutlink_check_flow(AVFilterLink *inlink, AVFilterLink *outlink);
/**
* Perform any additional setup required for hardware frames.
*
* link->hw_frames_ctx must be set before calling this function.
* Inside link->hw_frames_ctx, the fields format, sw_format, width and
* height must be set. If dynamically allocated pools are not supported,
* then initial_pool_size must also be set, to the minimum hardware frame
* pool size necessary for the filter to work (taking into account any
* frames which need to stored for use in operations as appropriate). If
* default_pool_size is nonzero, then it will be used as the pool size if
* no other modification takes place (this can be used to preserve
* compatibility).
*/
int ff_filter_init_hw_frames(AVFilterContext *avctx, AVFilterLink *link,
int default_pool_size);
/**
* Generic processing of user supplied commands that are set
* in the same way as the filter options.
* NOTE: 'enable' option is handled separately, and not by
* this function.
*/
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd,
const char *arg, char *res, int res_len, int flags);
/**
* Get number of threads for current filter instance.
* This number is always same or less than graph->nb_threads.
*/
int ff_filter_get_nb_threads(AVFilterContext *ctx) av_pure;
/**
* Send a frame of data to the next filter.
*
* @param link the output link over which the data is being sent
* @param frame a reference to the buffer of data being sent. The
* receiving filter will free this reference when it no longer
* needs it or pass it on to the next filter.
*
* @return >= 0 on success, a negative AVERROR on error. The receiving filter
* is responsible for unreferencing frame in case of error.
*/
int ff_filter_frame(AVFilterLink *link, AVFrame *frame);
/**
* Request an input frame from the filter at the other end of the link.
*
* This function must not be used by filters using the activate callback,
* use ff_link_set_frame_wanted() instead.
*
* The input filter may pass the request on to its inputs, fulfill the
* request from an internal buffer or any other means specific to its function.
*
* When the end of a stream is reached AVERROR_EOF is returned and no further
* frames are returned after that.
*
* When a filter is unable to output a frame for example due to its sources
* being unable to do so or because it depends on external means pushing data
* into it then AVERROR(EAGAIN) is returned.
* It is important that a AVERROR(EAGAIN) return is returned all the way to the
* caller (generally eventually a user application) as this step may (but does
* not have to be) necessary to provide the input with the next frame.
*
* If a request is successful then some progress has been made towards
* providing a frame on the link (through ff_filter_frame()). A filter that
* needs several frames to produce one is allowed to return success if one
* more frame has been processed but no output has been produced yet. A
* filter is also allowed to simply forward a success return value.
*
* @param link the input link
* @return zero on success
* AVERROR_EOF on end of file
* AVERROR(EAGAIN) if the previous filter cannot output a frame
* currently and can neither guarantee that EOF has been reached.
*/
int ff_request_frame(AVFilterLink *link);
/**
* Append a new input/output pad to the filter's list of such pads.
*
* The *_free_name versions will set the AVFILTERPAD_FLAG_FREE_NAME flag
* ensuring that the name will be freed generically (even on insertion error).
*/
int ff_append_inpad (AVFilterContext *f, AVFilterPad *p);
int ff_append_outpad(AVFilterContext *f, AVFilterPad *p);
int ff_append_inpad_free_name (AVFilterContext *f, AVFilterPad *p);
int ff_append_outpad_free_name(AVFilterContext *f, AVFilterPad *p);
/**
* Tell if an integer is contained in the provided -1-terminated list of integers.
* This is useful for determining (for instance) if an AVPixelFormat is in an
* array of supported formats.
*
* @param fmt provided format
* @param fmts -1-terminated list of formats
* @return 1 if present, 0 if absent
*/
int ff_fmt_is_in(int fmt, const int *fmts);
int ff_filter_execute(AVFilterContext *ctx, avfilter_action_func *func,
void *arg, int *ret, int nb_jobs);
#endif /* AVFILTER_FILTERS_H */