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Diffstat (limited to 'thirdparties/iphone/include/libavfilter/avfilter.h')
-rw-r--r-- | thirdparties/iphone/include/libavfilter/avfilter.h | 863 |
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diff --git a/thirdparties/iphone/include/libavfilter/avfilter.h b/thirdparties/iphone/include/libavfilter/avfilter.h new file mode 100644 index 0000000..d66bc00 --- /dev/null +++ b/thirdparties/iphone/include/libavfilter/avfilter.h @@ -0,0 +1,863 @@ +/* + * 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 + +#include <stddef.h> + +#include "libavutil/avutil.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 +} 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 +} 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. + * + * 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; + + /** + * 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. + * + * The reference given as argument is also available in link->cur_buf. + * It can be stored elsewhere or given away, but then clearing + * link->cur_buf is advised, as it is automatically unreferenced. + * The reference must not be unreferenced before end_frame(), as it may + * still be in use by the automatic copy mechanism. + * + * 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. + * 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 +#endif + unsigned nb_outputs; ///< number of output pads + + void *priv; ///< private data for use by the filter + + struct AVFilterCommand *command_queue; +}; + +/** + * 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 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 and channel layouts 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 and + * channel_layout members, 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; + + /** + * The buffer reference to the frame sent across the link by the + * source filter, which is read by the destination filter. It is + * automatically set up by ff_start_frame(). + * + * Depending on the permissions, it may either be the same as + * src_buf or an automatic copy of it. + * + * It is automatically freed by the filter system when calling + * ff_end_frame(). In case you save the buffer reference + * internally (e.g. if you cache it for later reuse), or give it + * away (e.g. if you pass the reference to the next filter) it + * must be set to NULL before calling ff_end_frame(). + */ + AVFilterBufferRef *cur_buf; + + /** + * The buffer reference to the frame which is sent to output by + * the source filter. + * + * If no start_frame callback is defined on a link, + * ff_start_frame() will automatically request a new buffer on the + * first output link of the destination filter. The reference to + * the buffer so obtained is stored in the out_buf field on the + * output link. + * + * It can also be set by the filter code in case the filter needs + * to access the output buffer later. For example the filter code + * may set it in a custom start_frame, and access it in + * draw_slice. + * + * It is automatically freed by the filter system in + * ff_end_frame(). + */ + AVFilterBufferRef *out_buf; + + struct AVFilterPool *pool; + + /** + * Graph the filter belongs to. + */ + struct AVFilterGraph *graph; + + /** + * Current timestamp of the link, as defined by the most recent + * frame(s), in AV_TIME_BASE units. + */ + int64_t current_pts; + + /** + * Index in the age array. + */ + int age_index; + + /** + * Frame rate of the stream on the link, or 1/0 if unknown; + * if left to 0/0, will be automatically be 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. + * 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; + + /** + * Buffer partially filled with samples to achieve a fixed/minimum size. + */ + AVFilterBufferRef *partial_buf; + + /** + * Size of the partial buffer to allocate. + * Must be between min_samples and max_samples. + */ + int partial_buf_size; + + /** + * Minimum number of samples to filter at once. If filter_samples() is + * called with fewer samples, it will accumulate them in partial_buf. + * This field and the related ones must not be changed after filtering + * has started. + * If 0, all related fields are ignored. + */ + int min_samples; + + /** + * Maximum number of samples to filter at once. If filter_samples() is + * called with more samples, it will split them. + */ + int max_samples; + + /** + * The buffer reference currently being received across the link by the + * destination 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 *cur_buf_copy; + + /** + * True if the link is closed. + * If set, all attemps of start_frame, filter_samples or request_frame + * will fail with AVERROR_EOF, and if necessary the reference will be + * destroyed. + * If request_frame returns AVERROR_EOF, this flag is set on the + * corresponding link. + * It can be set also be set by either the source or the destination + * filter. + */ + int closed; +}; + +/** + * 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); + +/** + * Free the link in *link, and set its pointer to NULL. + */ +void avfilter_link_free(AVFilterLink **link); + +/** + * Set the closed field of a link. + */ +void avfilter_link_set_closed(AVFilterLink *link, int closed); + +/** + * 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 * const data[4], const 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); + + +#define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically +#define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw) + +/** + * Make the filter instance process a command. + * It is recommended to use avfilter_graph_send_command(). + */ +int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags); + +/** 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 successful, 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); + +#endif /* AVFILTER_AVFILTER_H */ |