/* * filter layer * Copyright (c) 2007 Bobby Bingham * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVFILTER_AVFILTER_H #define AVFILTER_AVFILTER_H #include "libavutil/avutil.h" #include "libavutil/log.h" #include "libavutil/samplefmt.h" #include "libavutil/pixfmt.h" #include "libavutil/rational.h" #include "libavcodec/avcodec.h" #include #include "libavfilter/version.h" /** * Return the LIBAVFILTER_VERSION_INT constant. */ unsigned avfilter_version(void); /** * Return the libavfilter build-time configuration. */ const char *avfilter_configuration(void); /** * Return the libavfilter license. */ const char *avfilter_license(void); typedef struct AVFilterContext AVFilterContext; typedef struct AVFilterLink AVFilterLink; typedef struct AVFilterPad AVFilterPad; typedef struct AVFilterFormats AVFilterFormats; /** * A reference-counted buffer data type used by the filter system. Filters * should not store pointers to this structure directly, but instead use the * AVFilterBufferRef structure below. */ typedef struct AVFilterBuffer { uint8_t *data[8]; ///< buffer data for each plane/channel /** * pointers to the data planes/channels. * * For video, this should simply point to data[]. * * For planar audio, each channel has a separate data pointer, and * linesize[0] contains the size of each channel buffer. * For packed audio, there is just one data pointer, and linesize[0] * contains the total size of the buffer for all channels. * * Note: Both data and extended_data will always be set, but for planar * audio with more channels that can fit in data, extended_data must be used * in order to access all channels. */ uint8_t **extended_data; int linesize[8]; ///< number of bytes per line /** private data to be used by a custom free function */ void *priv; /** * A pointer to the function to deallocate this buffer if the default * function is not sufficient. This could, for example, add the memory * back into a memory pool to be reused later without the overhead of * reallocating it from scratch. */ void (*free)(struct AVFilterBuffer *buf); int format; ///< media format int w, h; ///< width and height of the allocated buffer unsigned refcount; ///< number of references to this buffer } AVFilterBuffer; #define AV_PERM_READ 0x01 ///< can read from the buffer #define AV_PERM_WRITE 0x02 ///< can write to the buffer #define AV_PERM_PRESERVE 0x04 ///< nobody else can overwrite the buffer #define AV_PERM_REUSE 0x08 ///< can output the buffer multiple times, with the same contents each time #define AV_PERM_REUSE2 0x10 ///< can output the buffer multiple times, modified each time #define AV_PERM_NEG_LINESIZES 0x20 ///< the buffer requested can have negative linesizes /** * Audio specific properties in a reference to an AVFilterBuffer. Since * AVFilterBufferRef is common to different media formats, audio specific * per reference properties must be separated out. */ typedef struct AVFilterBufferRefAudioProps { uint64_t channel_layout; ///< channel layout of audio buffer int nb_samples; ///< number of audio samples int sample_rate; ///< audio buffer sample rate int planar; ///< audio buffer - planar or packed } AVFilterBufferRefAudioProps; /** * Video specific properties in a reference to an AVFilterBuffer. Since * AVFilterBufferRef is common to different media formats, video specific * per reference properties must be separated out. */ typedef struct AVFilterBufferRefVideoProps { int w; ///< image width int h; ///< image height AVRational pixel_aspect; ///< pixel aspect ratio int interlaced; ///< is frame interlaced int top_field_first; ///< field order enum AVPictureType pict_type; ///< picture type of the frame int key_frame; ///< 1 -> keyframe, 0-> not } AVFilterBufferRefVideoProps; /** * A reference to an AVFilterBuffer. Since filters can manipulate the origin of * a buffer to, for example, crop image without any memcpy, the buffer origin * and dimensions are per-reference properties. Linesize is also useful for * image flipping, frame to field filters, etc, and so is also per-reference. * * TODO: add anything necessary for frame reordering */ typedef struct AVFilterBufferRef { AVFilterBuffer *buf; ///< the buffer that this is a reference to uint8_t *data[8]; ///< picture/audio data for each plane /** * pointers to the data planes/channels. * * For video, this should simply point to data[]. * * For planar audio, each channel has a separate data pointer, and * linesize[0] contains the size of each channel buffer. * For packed audio, there is just one data pointer, and linesize[0] * contains the total size of the buffer for all channels. * * Note: Both data and extended_data will always be set, but for planar * audio with more channels that can fit in data, extended_data must be used * in order to access all channels. */ uint8_t **extended_data; int linesize[8]; ///< number of bytes per line AVFilterBufferRefVideoProps *video; ///< video buffer specific properties AVFilterBufferRefAudioProps *audio; ///< audio buffer specific properties /** * presentation timestamp. The time unit may change during * filtering, as it is specified in the link and the filter code * may need to rescale the PTS accordingly. */ int64_t pts; int64_t pos; ///< byte position in stream, -1 if unknown int format; ///< media format int perms; ///< permissions, see the AV_PERM_* flags enum AVMediaType type; ///< media type of buffer data } AVFilterBufferRef; /** * Copy properties of src to dst, without copying the actual data */ void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, AVFilterBufferRef *src); /** * Add a new reference to a buffer. * * @param ref an existing reference to the buffer * @param pmask a bitmask containing the allowable permissions in the new * reference * @return a new reference to the buffer with the same properties as the * old, excluding any permissions denied by pmask */ AVFilterBufferRef *avfilter_ref_buffer(AVFilterBufferRef *ref, int pmask); /** * Remove a reference to a buffer. If this is the last reference to the * buffer, the buffer itself is also automatically freed. * * @param ref reference to the buffer, may be NULL * * @note it is recommended to use avfilter_unref_bufferp() instead of this * function */ void avfilter_unref_buffer(AVFilterBufferRef *ref); /** * Remove a reference to a buffer and set the pointer to NULL. * If this is the last reference to the buffer, the buffer itself * is also automatically freed. * * @param ref pointer to the buffer reference */ void avfilter_unref_bufferp(AVFilterBufferRef **ref); #if FF_API_AVFILTERPAD_PUBLIC /** * A filter pad used for either input or output. * * @warning this struct will be removed from public API. * users should call avfilter_pad_get_name() and avfilter_pad_get_type() * to access the name and type fields; there should be no need to access * any other fields from outside of libavfilter. */ 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; /** * Minimum required permissions on incoming buffers. Any buffer with * insufficient permissions will be automatically copied by the filter * system to a new buffer which provides the needed access permissions. * * Input pads only. */ int min_perms; /** * Permissions which are not accepted on incoming buffers. Any buffer * which has any of these permissions set will be automatically copied * by the filter system to a new buffer which does not have those * permissions. This can be used to easily disallow buffers with * AV_PERM_REUSE. * * Input pads only. */ int rej_perms; /** * Callback called before passing the first slice of a new frame. If * NULL, the filter layer will default to storing a reference to the * picture inside the link structure. * * Input video pads only. * * @return >= 0 on success, a negative AVERROR on error. picref will be * unreferenced by the caller in case of error. */ int (*start_frame)(AVFilterLink *link, AVFilterBufferRef *picref); /** * Callback function to get a video buffer. If NULL, the filter system will * use avfilter_default_get_video_buffer(). * * Input video pads only. */ AVFilterBufferRef *(*get_video_buffer)(AVFilterLink *link, int perms, int w, int h); /** * Callback function to get an audio buffer. If NULL, the filter system will * use avfilter_default_get_audio_buffer(). * * Input audio pads only. */ AVFilterBufferRef *(*get_audio_buffer)(AVFilterLink *link, int perms, int nb_samples); /** * Callback called after the slices of a frame are completely sent. If * NULL, the filter layer will default to releasing the reference stored * in the link structure during start_frame(). * * Input video pads only. * * @return >= 0 on success, a negative AVERROR on error. */ int (*end_frame)(AVFilterLink *link); /** * Slice drawing callback. This is where a filter receives video data * and should do its processing. * * Input video pads only. * * @return >= 0 on success, a negative AVERROR on error. */ int (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir); /** * Samples filtering callback. This is where a filter receives audio data * and should do its processing. * * Input audio pads only. * * @return >= 0 on success, a negative AVERROR on error. This function * must ensure that samplesref is properly unreferenced on error if it * hasn't been passed on to another filter. */ int (*filter_samples)(AVFilterLink *link, AVFilterBufferRef *samplesref); /** * Frame poll callback. This returns the number of immediately available * samples. It should return a positive value if the next request_frame() * is guaranteed to return one frame (with no delay). * * Defaults to just calling the source poll_frame() method. * * Output pads only. */ int (*poll_frame)(AVFilterLink *link); /** * Frame request callback. A call to this should result in at least one * frame being 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); /** * The filter expects a fifo to be inserted on its input link, * typically because it has a delay. * * input pads only. */ int needs_fifo; }; #endif /** * Get the name of an AVFilterPad. * * @param pads an array of AVFilterPads * @param pad_idx index of the pad in the array it; is the caller's * responsibility to ensure the index is valid * * @return name of the pad_idx'th pad in pads */ const char *avfilter_pad_get_name(AVFilterPad *pads, int pad_idx); /** * Get the type of an AVFilterPad. * * @param pads an array of AVFilterPads * @param pad_idx index of the pad in the array; it is the caller's * responsibility to ensure the index is valid * * @return type of the pad_idx'th pad in pads */ enum AVMediaType avfilter_pad_get_type(AVFilterPad *pads, int pad_idx); /** * Filter definition. This defines the pads a filter contains, and all the * callback functions used to interact with the filter. */ typedef struct AVFilter { const char *name; ///< filter name /** * A description for the filter. You should use the * NULL_IF_CONFIG_SMALL() macro to define it. */ const char *description; const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none /***************************************************************** * All fields below this line are not part of the public API. They * may not be used outside of libavfilter and can be changed and * removed at will. * New public fields should be added right above. ***************************************************************** */ /** * Filter initialization function. Args contains the user-supplied * parameters. FIXME: maybe an AVOption-based system would be better? */ int (*init)(AVFilterContext *ctx, const char *args); /** * Filter uninitialization function. Should deallocate any memory held * by the filter, release any buffer references, etc. This does not need * to deallocate the AVFilterContext->priv memory itself. */ void (*uninit)(AVFilterContext *ctx); /** * Queries formats supported by the filter and its pads, and sets the * in_formats for links connected to its output pads, and out_formats * for links connected to its input pads. * * @return zero on success, a negative value corresponding to an * AVERROR code otherwise */ int (*query_formats)(AVFilterContext *); int priv_size; ///< size of private data to allocate for the filter } AVFilter; /** An instance of a filter */ struct AVFilterContext { const AVClass *av_class; ///< needed for av_log() AVFilter *filter; ///< the AVFilter of which this is an instance char *name; ///< name of this filter instance AVFilterPad *input_pads; ///< array of input pads AVFilterLink **inputs; ///< array of pointers to input links #if FF_API_FOO_COUNT unsigned input_count; ///< @deprecated use nb_inputs #endif unsigned nb_inputs; ///< number of input pads AVFilterPad *output_pads; ///< array of output pads AVFilterLink **outputs; ///< array of pointers to output links #if FF_API_FOO_COUNT unsigned output_count; ///< @deprecated use nb_outputs #endif unsigned nb_outputs; ///< number of output pads void *priv; ///< private data for use by the filter }; /** * A link between two filters. This contains pointers to the source and * destination filters between which this link exists, and the indexes of * the pads involved. In addition, this link also contains the parameters * which have been negotiated and agreed upon between the filter, such as * image dimensions, format, etc. */ struct AVFilterLink { AVFilterContext *src; ///< source filter AVFilterPad *srcpad; ///< output pad on the source filter AVFilterContext *dst; ///< dest filter AVFilterPad *dstpad; ///< input pad on the dest filter enum AVMediaType type; ///< filter media type /* These parameters apply only to video */ int w; ///< agreed upon image width int h; ///< agreed upon image height AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio /* These two parameters apply only to audio */ uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/audioconvert.h) int sample_rate; ///< samples per second int format; ///< agreed upon media format /** * Define the time base used by the PTS of the frames/samples * which will pass through this link. * During the configuration stage, each filter is supposed to * change only the output timebase, while the timebase of the * input link is assumed to be an unchangeable property. */ AVRational time_base; /***************************************************************** * All fields below this line are not part of the public API. They * may not be used outside of libavfilter and can be changed and * removed at will. * New public fields should be added right above. ***************************************************************** */ /** * Lists of formats supported by the input and output filters respectively. * These lists are used for negotiating the format to actually be used, * which will be loaded into the format member, above, when chosen. */ AVFilterFormats *in_formats; AVFilterFormats *out_formats; /** * Lists of channel layouts and sample rates used for automatic * negotiation. */ AVFilterFormats *in_samplerates; AVFilterFormats *out_samplerates; struct AVFilterChannelLayouts *in_channel_layouts; struct AVFilterChannelLayouts *out_channel_layouts; /** * Audio only, the destination filter sets this to a non-zero value to * request that buffers with the given number of samples should be sent to * it. AVFilterPad.needs_fifo must also be set on the corresponding input * pad. * Last buffer before EOF will be padded with silence. */ int request_samples; /** stage of the initialization of the link properties (dimensions, etc) */ enum { AVLINK_UNINIT = 0, ///< not started AVLINK_STARTINIT, ///< started, but incomplete AVLINK_INIT ///< complete } init_state; /** * The buffer reference currently being sent across the link by the source * filter. This is used internally by the filter system to allow * automatic copying of buffers which do not have sufficient permissions * for the destination. This should not be accessed directly by the * filters. */ AVFilterBufferRef *src_buf; AVFilterBufferRef *cur_buf; AVFilterBufferRef *out_buf; }; /** * Link two filters together. * * @param src the source filter * @param srcpad index of the output pad on the source filter * @param dst the destination filter * @param dstpad index of the input pad on the destination filter * @return zero on success */ int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad); /** * Negotiate the media format, dimensions, etc of all inputs to a filter. * * @param filter the filter to negotiate the properties for its inputs * @return zero on successful negotiation */ int avfilter_config_links(AVFilterContext *filter); /** * Create a buffer reference wrapped around an already allocated image * buffer. * * @param data pointers to the planes of the image to reference * @param linesize linesizes for the planes of the image to reference * @param perms the required access permissions * @param w the width of the image specified by the data and linesize arrays * @param h the height of the image specified by the data and linesize arrays * @param format the pixel format of the image specified by the data and linesize arrays */ AVFilterBufferRef * avfilter_get_video_buffer_ref_from_arrays(uint8_t *data[4], int linesize[4], int perms, int w, int h, enum PixelFormat format); /** * Create an audio buffer reference wrapped around an already * allocated samples buffer. * * @param data pointers to the samples plane buffers * @param linesize linesize for the samples plane buffers * @param perms the required access permissions * @param nb_samples number of samples per channel * @param sample_fmt the format of each sample in the buffer to allocate * @param channel_layout the channel layout of the buffer */ AVFilterBufferRef *avfilter_get_audio_buffer_ref_from_arrays(uint8_t **data, int linesize, int perms, int nb_samples, enum AVSampleFormat sample_fmt, uint64_t channel_layout); /** Initialize the filter system. Register all builtin filters. */ void avfilter_register_all(void); /** Uninitialize the filter system. Unregister all filters. */ void avfilter_uninit(void); /** * Register a filter. This is only needed if you plan to use * avfilter_get_by_name later to lookup the AVFilter structure by name. A * filter can still by instantiated with avfilter_open even if it is not * registered. * * @param filter the filter to register * @return 0 if the registration was succesfull, a negative value * otherwise */ int avfilter_register(AVFilter *filter); /** * Get a filter definition matching the given name. * * @param name the filter name to find * @return the filter definition, if any matching one is registered. * NULL if none found. */ AVFilter *avfilter_get_by_name(const char *name); /** * If filter is NULL, returns a pointer to the first registered filter pointer, * if filter is non-NULL, returns the next pointer after filter. * If the returned pointer points to NULL, the last registered filter * was already reached. */ AVFilter **av_filter_next(AVFilter **filter); /** * Create a filter instance. * * @param filter_ctx put here a pointer to the created filter context * on success, NULL on failure * @param filter the filter to create an instance of * @param inst_name Name to give to the new instance. Can be NULL for none. * @return >= 0 in case of success, a negative error code otherwise */ int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name); /** * Initialize a filter. * * @param filter the filter to initialize * @param args A string of parameters to use when initializing the filter. * The format and meaning of this string varies by filter. * @param opaque Any extra non-string data needed by the filter. The meaning * of this parameter varies by filter. * @return zero on success */ int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque); /** * Free a filter context. * * @param filter the filter to free */ void avfilter_free(AVFilterContext *filter); /** * Insert a filter in the middle of an existing link. * * @param link the link into which the filter should be inserted * @param filt the filter to be inserted * @param filt_srcpad_idx the input pad on the filter to connect * @param filt_dstpad_idx the output pad on the filter to connect * @return zero on success */ int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt, unsigned filt_srcpad_idx, unsigned filt_dstpad_idx); /** * Copy the frame properties of src to dst, without copying the actual * image data. * * @return 0 on success, a negative number on error. */ int avfilter_copy_frame_props(AVFilterBufferRef *dst, const AVFrame *src); /** * Copy the frame properties and data pointers of src to dst, without copying * the actual data. * * @return 0 on success, a negative number on error. */ int avfilter_copy_buf_props(AVFrame *dst, const AVFilterBufferRef *src); #endif /* AVFILTER_AVFILTER_H */