| /* |
| * 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 |
| |
| #define LIBAVFILTER_VERSION_MAJOR 0 |
| #define LIBAVFILTER_VERSION_MINOR 4 |
| #define LIBAVFILTER_VERSION_MICRO 0 |
| |
| #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \ |
| LIBAVFILTER_VERSION_MINOR, \ |
| LIBAVFILTER_VERSION_MICRO) |
| #define LIBAVFILTER_VERSION AV_VERSION(LIBAVFILTER_VERSION_MAJOR, \ |
| LIBAVFILTER_VERSION_MINOR, \ |
| LIBAVFILTER_VERSION_MICRO) |
| #define LIBAVFILTER_BUILD LIBAVFILTER_VERSION_INT |
| |
| #include <stddef.h> |
| #include "libavcodec/avcodec.h" |
| |
| /** |
| * Returns the LIBAVFILTER_VERSION_INT constant. |
| */ |
| unsigned avfilter_version(void); |
| |
| typedef struct AVFilterContext AVFilterContext; |
| typedef struct AVFilterLink AVFilterLink; |
| typedef struct AVFilterPad AVFilterPad; |
| |
| /* TODO: look for other flags which may be useful in this structure (interlace |
| * flags, etc) |
| */ |
| /** |
| * A reference-counted picture data type used by the filter system. Filters |
| * should not store pointers to this structure directly, but instead use the |
| * AVFilterPicRef structure below. |
| */ |
| typedef struct AVFilterPic |
| { |
| uint8_t *data[4]; ///< picture data for each plane |
| int linesize[4]; ///< number of bytes per line |
| enum PixelFormat format; ///< colorspace |
| |
| unsigned refcount; ///< number of references to this image |
| |
| /** private data to be used by a custom free function */ |
| void *priv; |
| /** |
| * A pointer to the function to deallocate this image 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 AVFilterPic *pic); |
| } AVFilterPic; |
| |
| /** |
| * A reference to an AVFilterPic. Since filters can manipulate the origin of |
| * a picture to, for example, crop image without any memcpy, the picture 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 AVFilterPicRef |
| { |
| AVFilterPic *pic; ///< the picture that this is a reference to |
| uint8_t *data[4]; ///< picture data for each plane |
| int linesize[4]; ///< number of bytes per line |
| int w; ///< image width |
| int h; ///< image height |
| |
| int64_t pts; ///< presentation timestamp in units of 1/AV_TIME_BASE |
| |
| AVRational pixel_aspect; ///< pixel aspect ratio |
| |
| int perms; ///< permissions |
| #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 |
| } AVFilterPicRef; |
| |
| /** |
| * Add a new reference to a picture. |
| * @param ref an existing reference to the picture |
| * @param pmask a bitmask containing the allowable permissions in the new |
| * reference |
| * @return a new reference to the picture with the same properties as the |
| * old, excluding any permissions denied by pmask |
| */ |
| AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask); |
| |
| /** |
| * Remove a reference to a picture. If this is the last reference to the |
| * picture, the picture itself is also automatically freed. |
| * @param ref reference to the picture |
| */ |
| void avfilter_unref_pic(AVFilterPicRef *ref); |
| |
| /** |
| * A list of supported formats for one end of a filter link. This is used |
| * during the format negotiation process to try to pick the best format to |
| * use to minimize the number of necessary conversions. Each filter gives a |
| * list of the formats supported by each input and output pad. The list |
| * given for each pad need not be distinct - they may be references to the |
| * same list of formats, as is often the case when a filter supports multiple |
| * formats, but will always output the same format as it is given in input. |
| * |
| * In this way, a list of possible input formats and a list of possible |
| * output formats are associated with each link. When a set of formats is |
| * negotiated over a link, the input and output lists are merged to form a |
| * new list containing only the common elements of each list. In the case |
| * that there were no common elements, a format conversion is necessary. |
| * Otherwise, the lists are merged, and all other links which reference |
| * either of the format lists involved in the merge are also affected. |
| * |
| * For example, consider the filter chain: |
| * filter (a) --> (b) filter (b) --> (c) filter |
| * |
| * where the letters in parenthesis indicate a list of formats supported on |
| * the input or output of the link. Suppose the lists are as follows: |
| * (a) = {A, B} |
| * (b) = {A, B, C} |
| * (c) = {B, C} |
| * |
| * First, the first link's lists are merged, yielding: |
| * filter (a) --> (a) filter (a) --> (c) filter |
| * |
| * Notice that format list (b) now refers to the same list as filter list (a). |
| * Next, the lists for the second link are merged, yielding: |
| * filter (a) --> (a) filter (a) --> (a) filter |
| * |
| * where (a) = {B}. |
| * |
| * Unfortunately, when the format lists at the two ends of a link are merged, |
| * we must ensure that all links which reference either pre-merge format list |
| * get updated as well. Therefore, we have the format list structure store a |
| * pointer to each of the pointers to itself. |
| */ |
| typedef struct AVFilterFormats AVFilterFormats; |
| struct AVFilterFormats |
| { |
| unsigned format_count; ///< number of formats |
| int *formats; ///< list of formats |
| |
| unsigned refcount; ///< number of references to this list |
| AVFilterFormats ***refs; ///< references to this list |
| }; |
| |
| /** |
| * Helper function to create a list of supported formats. This is intended |
| * for use in AVFilter->query_formats(). |
| * @param len the number of formats supported |
| * @param ... a list of the supported formats |
| * @return the format list, with no existing references |
| */ |
| AVFilterFormats *avfilter_make_format_list(int len, ...); |
| |
| /** |
| * Returns a list of all colorspaces supported by FFmpeg. |
| */ |
| AVFilterFormats *avfilter_all_colorspaces(void); |
| |
| /** |
| * Returns a format list which contains the intersection of the formats of |
| * a and b. Also, all the references of a, all the references of b, and |
| * a and b themselves will be deallocated. |
| * |
| * If a and b do not share any common formats, neither is modified, and NULL |
| * is returned. |
| */ |
| AVFilterFormats *avfilter_merge_formats(AVFilterFormats *a, AVFilterFormats *b); |
| |
| /** |
| * Adds *ref as a new reference to formats. |
| * That is the pointers will point like in the ascii art below: |
| * ________ |
| * |formats |<--------. |
| * | ____ | ____|___________________ |
| * | |refs| | | __|_ |
| * | |* * | | | | | | AVFilterLink |
| * | |* *--------->|*ref| |
| * | |____| | | |____| |
| * |________| |________________________ |
| */ |
| void avfilter_formats_ref(AVFilterFormats *formats, AVFilterFormats **ref); |
| |
| /** |
| * Remove *ref as a reference to the format list it currently points to, |
| * deallocate that list if this was the last reference, and set *ref to NULL. |
| * |
| * Before After |
| * ________ ________ NULL |
| * |formats |<--------. |formats | ^ |
| * | ____ | ____|________________ | ____ | ____|________________ |
| * | |refs| | | __|_ | |refs| | | __|_ |
| * | |* * | | | | | | AVFilterLink | |* * | | | | | | AVFilterLink |
| * | |* *--------->|*ref| | |* | | | |*ref| |
| * | |____| | | |____| | |____| | | |____| |
| * |________| |_____________________ |________| |_____________________ |
| */ |
| void avfilter_formats_unref(AVFilterFormats **ref); |
| |
| /** |
| * |
| * Before After |
| * ________ ________ |
| * |formats |<---------. |formats |<---------. |
| * | ____ | ___|___ | ____ | ___|___ |
| * | |refs| | | | | | |refs| | | | | NULL |
| * | |* *--------->|*oldref| | |* *--------->|*newref| ^ |
| * | |* * | | |_______| | |* * | | |_______| ___|___ |
| * | |____| | | |____| | | | | |
| * |________| |________| |*oldref| |
| * |_______| |
| */ |
| void avfilter_formats_changeref(AVFilterFormats **oldref, |
| AVFilterFormats **newref); |
| |
| /** |
| * 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. Only video supported now, hopefully someone will |
| * add audio in the future. |
| */ |
| enum CodecType 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. |
| */ |
| void (*start_frame)(AVFilterLink *link, AVFilterPicRef *picref); |
| |
| /** |
| * Callback function to get a buffer. If NULL, the filter system will |
| * handle buffer requests. |
| * |
| * Input video pads only. |
| */ |
| AVFilterPicRef *(*get_video_buffer)(AVFilterLink *link, int perms); |
| |
| /** |
| * 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. |
| */ |
| void (*end_frame)(AVFilterLink *link); |
| |
| /** |
| * Slice drawing callback. This is where a filter receives video data |
| * and should do its processing. |
| * |
| * Input video pads only. |
| */ |
| void (*draw_slice)(AVFilterLink *link, int y, int height); |
| |
| /** |
| * Frame poll callback. This returns the number of immediately available |
| * frames. 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 video 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 video 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); |
| }; |
| |
| /** default handler for start_frame() for video inputs */ |
| void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref); |
| /** default handler for draw_slice() for video inputs */ |
| void avfilter_default_draw_slice(AVFilterLink *link, int y, int h); |
| /** default handler for end_frame() for video inputs */ |
| void avfilter_default_end_frame(AVFilterLink *link); |
| /** default handler for config_props() for video outputs */ |
| int avfilter_default_config_output_link(AVFilterLink *link); |
| /** default handler for config_props() for video inputs */ |
| int avfilter_default_config_input_link (AVFilterLink *link); |
| /** default handler for get_video_buffer() for video inputs */ |
| AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link, |
| int perms); |
| /** |
| * A helper for query_formats() which sets all links to the same list of |
| * formats. If there are no links hooked to this filter, the list of formats is |
| * freed. |
| */ |
| void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats); |
| /** Default handler for query_formats() */ |
| int avfilter_default_query_formats(AVFilterContext *ctx); |
| |
| /** |
| * Filter definition. This defines the pads a filter contains, and all the |
| * callback functions used to interact with the filter. |
| */ |
| typedef struct |
| { |
| const char *name; ///< filter name |
| |
| int priv_size; ///< size of private data to allocate for the filter |
| |
| /** |
| * Filter initialization function. Args contains the user-supplied |
| * parameters. FIXME: maybe an AVOption-based system would be better? |
| * opaque is data provided by the code requesting creation of the filter, |
| * and is used to pass data to the filter. |
| */ |
| int (*init)(AVFilterContext *ctx, const char *args, void *opaque); |
| |
| /** |
| * Filter uninitialization function. Should deallocate any memory held |
| * by the filter, release any picture references, etc. This does not need |
| * to deallocate the AVFilterContext->priv memory itself. |
| */ |
| void (*uninit)(AVFilterContext *ctx); |
| |
| /** |
| * Query formats supported by the filter and its pads. Should set the |
| * in_formats for links connected to its output pads, and out_formats |
| * for links connected to its input pads. |
| * |
| * Should return zero on success. |
| */ |
| int (*query_formats)(AVFilterContext *); |
| |
| const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none |
| const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none |
| } 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 |
| |
| unsigned input_count; ///< number of input pads |
| AVFilterPad *input_pads; ///< array of input pads |
| AVFilterLink **inputs; ///< array of pointers to input links |
| |
| unsigned output_count; ///< number of output pads |
| AVFilterPad *output_pads; ///< array of output pads |
| AVFilterLink **outputs; ///< array of pointers to output links |
| |
| 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 |
| unsigned int srcpad; ///< index of the output pad on the source filter |
| |
| AVFilterContext *dst; ///< dest filter |
| unsigned int dstpad; ///< index of the input pad on the dest filter |
| |
| /** 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; |
| |
| int w; ///< agreed upon image width |
| int h; ///< agreed upon image height |
| enum PixelFormat format; ///< agreed upon image colorspace |
| |
| /** |
| * 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; |
| |
| /** |
| * The picture reference currently being sent across the link by the source |
| * filter. This is used internally by the filter system to allow |
| * automatic copying of pictures which do not have sufficient permissions |
| * for the destination. This should not be accessed directly by the |
| * filters. |
| */ |
| AVFilterPicRef *srcpic; |
| |
| AVFilterPicRef *cur_pic; |
| AVFilterPicRef *outpic; |
| }; |
| |
| /** |
| * 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 colorspace, 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); |
| |
| /** |
| * Request a picture buffer with a specific set of permissions. |
| * @param link the output link to the filter from which the picture will |
| * be requested |
| * @param perms the required access permissions |
| * @return A reference to the picture. This must be unreferenced with |
| * avfilter_unref_pic when you are finished with it. |
| */ |
| AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms); |
| |
| /** |
| * Request an input frame from the filter at the other end of the link. |
| * @param link the input link |
| * @return zero on success |
| */ |
| int avfilter_request_frame(AVFilterLink *link); |
| |
| /** |
| * Poll a frame from the filter chain. |
| * @param link the input link |
| * @return the number of immediately available frames, a negative |
| * number in case of error |
| */ |
| int avfilter_poll_frame(AVFilterLink *link); |
| |
| /** |
| * Notify the next filter of the start of a frame. |
| * @param link the output link the frame will be sent over |
| * @param picref A reference to the frame about to be sent. The data for this |
| * frame need only be valid once draw_slice() is called for that |
| * portion. The receiving filter will free this reference when |
| * it no longer needs it. |
| */ |
| void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref); |
| |
| /** |
| * Notify the next filter that the current frame has finished. |
| * @param link the output link the frame was sent over |
| */ |
| void avfilter_end_frame(AVFilterLink *link); |
| |
| /** |
| * Send a slice to the next filter. |
| * @param link the output link over which the frame is being sent |
| * @param y offset in pixels from the top of the image for this slice |
| * @param h height of this slice in pixels |
| */ |
| void avfilter_draw_slice(AVFilterLink *link, int y, int h); |
| |
| /** Initialize the filter system. Registers all builtin filters */ |
| void avfilter_register_all(void); |
| |
| /** Uninitialize the filter system. Unregisters 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 |
| */ |
| void avfilter_register(AVFilter *filter); |
| |
| /** |
| * Gets 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); |
| |
| /** |
| * Create a filter instance. |
| * @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 Pointer to the new instance on success. NULL on failure. |
| */ |
| AVFilterContext *avfilter_open(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); |
| |
| /** |
| * Destroy a filter. |
| * @param filter the filter to destroy |
| */ |
| void avfilter_destroy(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 in the input pad on the filter to connect |
| * @param out the output pad on the filter to connect |
| * @return zero on success |
| */ |
| int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt, |
| unsigned in, unsigned out); |
| |
| /** |
| * Insert a new pad. |
| * @param idx Insertion point. Pad is inserted at the end if this point |
| * is beyond the end of the list of pads. |
| * @param count Pointer to the number of pads in the list |
| * @param padidx_off Offset within an AVFilterLink structure to the element |
| * to increment when inserting a new pad causes link |
| * numbering to change |
| * @param pads Pointer to the pointer to the beginning of the list of pads |
| * @param links Pointer to the pointer to the beginning of the list of links |
| * @param newpad The new pad to add. A copy is made when adding. |
| */ |
| void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off, |
| AVFilterPad **pads, AVFilterLink ***links, |
| AVFilterPad *newpad); |
| |
| /** Insert a new input pad for the filter. */ |
| static inline void avfilter_insert_inpad(AVFilterContext *f, unsigned index, |
| AVFilterPad *p) |
| { |
| avfilter_insert_pad(index, &f->input_count, offsetof(AVFilterLink, dstpad), |
| &f->input_pads, &f->inputs, p); |
| } |
| |
| /** Insert a new output pad for the filter. */ |
| static inline void avfilter_insert_outpad(AVFilterContext *f, unsigned index, |
| AVFilterPad *p) |
| { |
| avfilter_insert_pad(index, &f->output_count, offsetof(AVFilterLink, srcpad), |
| &f->output_pads, &f->outputs, p); |
| } |
| |
| #endif /* AVFILTER_AVFILTER_H */ |
