/* * filter layer * Copyright (c) 2007 Bobby Bingham * * 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_AVFILTER_H#define AVFILTER_AVFILTER_H /** * @file * @ingroup lavfi * external API header */ /** * @defgroup lavfi Libavfilter * @{ */ #include <stddef.h> #include "libavutil/avutil.h"#include "libavutil/dict.h"#include "libavutil/log.h"#include "libavutil/samplefmt.h"#include "libavutil/pixfmt.h"#include "libavutil/rational.h" #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); /** * Get the class for the AVFilterContext struct. */const AVClass *avfilter_get_class(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#define AV_PERM_ALIGN 0x40 ///< the buffer must be aligned #define AVFILTER_ALIGN 16 //not part of ABI /** * 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 per channel int sample_rate; ///< audio buffer sample rate int channels; ///< number of channels (do not access directly)} 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 sample_aspect_ratio; ///< sample 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 int qp_table_linesize; ///< qp_table stride int qp_table_size; ///< qp_table size int8_t *qp_table; ///< array of Quantization Parameters} 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 AVDictionary *metadata; ///< dictionary containing metadata key=value tags} 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); /** * Get the number of channels of a buffer reference. */int avfilter_ref_get_channels(AVFilterBufferRef *ref); #if FF_API_AVFILTERPAD_PUBLIC/** * A filter pad used for either input or output. * * See doc/filter_design.txt for details on how to implement the methods. * * @warning this struct might 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; /** * Input pads: * 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. * * Output pads: * Guaranteed permissions on outgoing buffers. Any buffer pushed on the * link must have at least these permissions; this fact is checked by * asserts. It can be used to optimize buffer allocation. */ int min_perms; /** * Input pads: * 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. * * Output pads: * Permissions which are automatically removed on outgoing buffers. It * can be used to optimize buffer allocation. */ int rej_perms; /** * @deprecated unused */ int (*start_frame)(AVFilterLink *link, AVFilterBufferRef *picref); /** * Callback function to get a video buffer. If NULL, the filter system will * use ff_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 ff_default_get_audio_buffer(). * * Input audio pads only. */ AVFilterBufferRef *(*get_audio_buffer)(AVFilterLink *link, int perms, int nb_samples); /** * @deprecated unused */ int (*end_frame)(AVFilterLink *link); /** * @deprecated unused */ int (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir); /** * 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, AVFilterBufferRef *frame); /** * 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. * See ff_request_frame() for the error codes with a specific * meaning. * * Output pads only. */ int (*request_frame)(AVFilterLink *link); /** * Link configuration callback. * * For output pads, this should set the following link properties: * video: width, height, sample_aspect_ratio, time_base * audio: sample_rate. * * This should NOT set properties such as format, channel_layout, etc which * are 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 pads, 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/layouts supported by the filter and its pads, and sets * the in_formats/in_chlayouts for links connected to its output pads, * and out_formats/out_chlayouts 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 /** * Make the filter instance process a command. * * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only * @param arg the argument for the command * @param res a buffer with size res_size where the filter(s) can return a response. This must not change when the command is not supported. * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be * time consuming then a filter should treat it like an unsupported command * * @returns >=0 on success otherwise an error code. * AVERROR(ENOSYS) on unsupported commands */ int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags); /** * Filter initialization function, alternative to the init() * callback. Args contains the user-supplied parameters, opaque is * used for providing binary data. */ int (*init_opaque)(AVFilterContext *ctx, const char *args, void *opaque); const AVClass *priv_class; ///< private class, containing filter specific options} 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_outputsLines 1–500 of 873. Load more
/* * filter layer * Copyright (c) 2007 Bobby Bingham * * 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_AVFILTER_H #define AVFILTER_AVFILTER_H /** * @file * @ingroup lavfi * external API header */ /** * @defgroup lavfi Libavfilter * @{ */ #include <stddef.h> #include "libavutil/avutil.h" #include "libavutil/dict.h" #include "libavutil/log.h" #include "libavutil/samplefmt.h" #include "libavutil/pixfmt.h" #include "libavutil/rational.h" #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); /** * Get the class for the AVFilterContext struct. */ const AVClass *avfilter_get_class(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 #define AV_PERM_ALIGN 0x40 ///< the buffer must be aligned #define AVFILTER_ALIGN 16 //not part of ABI /** * 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 per channel int sample_rate; ///< audio buffer sample rate int channels; ///< number of channels (do not access directly) } 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 sample_aspect_ratio; ///< sample 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 int qp_table_linesize; ///< qp_table stride int qp_table_size; ///< qp_table size int8_t *qp_table; ///< array of Quantization Parameters } 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 AVDictionary *metadata; ///< dictionary containing metadata key=value tags } 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); /** * Get the number of channels of a buffer reference. */ int avfilter_ref_get_channels(AVFilterBufferRef *ref); #if FF_API_AVFILTERPAD_PUBLIC /** * A filter pad used for either input or output. * * See doc/filter_design.txt for details on how to implement the methods. * * @warning this struct might 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; /** * Input pads: * 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. * * Output pads: * Guaranteed permissions on outgoing buffers. Any buffer pushed on the * link must have at least these permissions; this fact is checked by * asserts. It can be used to optimize buffer allocation. */ int min_perms; /** * Input pads: * 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. * * Output pads: * Permissions which are automatically removed on outgoing buffers. It * can be used to optimize buffer allocation. */ int rej_perms; /** * @deprecated unused */ int (*start_frame)(AVFilterLink *link, AVFilterBufferRef *picref); /** * Callback function to get a video buffer. If NULL, the filter system will * use ff_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 ff_default_get_audio_buffer(). * * Input audio pads only. */ AVFilterBufferRef *(*get_audio_buffer)(AVFilterLink *link, int perms, int nb_samples); /** * @deprecated unused */ int (*end_frame)(AVFilterLink *link); /** * @deprecated unused */ int (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir); /** * 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, AVFilterBufferRef *frame); /** * 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. * See ff_request_frame() for the error codes with a specific * meaning. * * Output pads only. */ int (*request_frame)(AVFilterLink *link); /** * Link configuration callback. * * For output pads, this should set the following link properties: * video: width, height, sample_aspect_ratio, time_base * audio: sample_rate. * * This should NOT set properties such as format, channel_layout, etc which * are 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 pads, 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/layouts supported by the filter and its pads, and sets * the in_formats/in_chlayouts for links connected to its output pads, * and out_formats/out_chlayouts 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 /** * Make the filter instance process a command. * * @param cmd the command to process, for handling simplicity all commands must be alphanumeric only * @param arg the argument for the command * @param res a buffer with size res_size where the filter(s) can return a response. This must not change when the command is not supported. * @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be * time consuming then a filter should treat it like an unsupported command * * @returns >=0 on success otherwise an error code. * AVERROR(ENOSYS) on unsupported commands */ int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags); /** * Filter initialization function, alternative to the init() * callback. Args contains the user-supplied parameters, opaque is * used for providing binary data. */ int (*init_opaque)(AVFilterContext *ctx, const char *args, void *opaque); const AVClass *priv_class; ///< private class, containing filter specific options } 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