X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavfilter%2Favfilter.h;h=b660be74f4777b0b34c62960654739ba9ce333d1;hb=d7ff2297184e455cca90cc830d1a8be2bb6f0f2b;hp=617e512a701f8ff7d17399168d952eef09b95aa7;hpb=a9c81431bdbb1eef04c8d0a292f90f1dd0b7587e;p=ffmpeg diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h index 617e512a701..b660be74f47 100644 --- a/libavfilter/avfilter.h +++ b/libavfilter/avfilter.h @@ -1,5 +1,5 @@ /* - * Filter layer + * filter layer * copyright (c) 2007 Bobby Bingham * * This file is part of FFmpeg. @@ -22,8 +22,20 @@ #ifndef FFMPEG_AVFILTER_H #define FFMPEG_AVFILTER_H +#define LIBAVFILTER_VERSION_MAJOR 0 +#define LIBAVFILTER_VERSION_MINOR 0 +#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 -#include "avcodec.h" +#include "libavcodec/avcodec.h" typedef struct AVFilterContext AVFilterContext; typedef struct AVFilterLink AVFilterLink; @@ -35,16 +47,24 @@ typedef struct AVFilterPad AVFilterPad; /** * 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 + * AVFilterPicRef structure below. */ typedef struct AVFilterPic { - uint8_t *data[4]; - int linesize[4]; ///< number of bytes per line - enum PixelFormat format; + uint8_t *data[4]; ///< picture data for each plane + int linesize[4]; ///< number of bytes per line + enum PixelFormat format; ///< colorspace - unsigned refcount; + 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; @@ -58,67 +78,212 @@ typedef struct AVFilterPic */ typedef struct AVFilterPicRef { - AVFilterPic *pic; - uint8_t *data[4]; - int linesize[4]; - int w, h; + 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 - int64_t pts; ///< presentation timestamp in milliseconds + 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 +#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 + * @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. + * @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 outut 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. And all the references of a and b, and a and b 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 oututs, but an - * input may have the same name as an output. + * 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. */ - char *name; + const char *name; /** * AVFilterPad type. Only video supported now, hopefully someone will * add audio in the future. */ - int type; -#define AV_PAD_VIDEO 0 + enum CodecType type; /** - * Callback to get a list of supported formats. The returned list should - * be terminated by -1. This is used for both input and output pads and - * is required for both. + * Minimum required permissions on incoming buffers. Any buffers 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 *(*query_formats)(AVFilterLink *link); + int min_perms; + + /** + * Permissions which are not accepted on incoming buffers. Any buffer + * which has any of these permissions set 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. Only required for input video pads. + * handle buffer requests. + * + * Input video pads only. */ AVFilterPicRef *(*get_video_buffer)(AVFilterLink *link, int perms); @@ -126,48 +291,85 @@ struct AVFilterPad * 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. Only required for input video pads. + * 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. */ - void (*draw_slice)(AVFilterLink *link, uint8_t *data[4], int y, int height); + 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. Video output pads only. + * frame being output over the given link. This should return zero on + * success, and another value on error. + * + * Output video pads only. */ - void (*request_frame)(AVFilterLink *link); + int (*request_frame)(AVFilterLink *link); /** - * Link configuration callback. For output pads, this should set the link - * properties such as width/height. NOTE: this should not set the format - * property - that is negotiated between filters by the filter system using - * the query_formats() callback. + * 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 default implementations of filter entry points */ +/** Default handler for start_frame() for video inputs */ void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref); +/** 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); -int *avfilter_default_query_output_formats(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 { - char *name; - char *author; + const char *name; ///< filter name - int priv_size; + int priv_size; ///< size of private data to allocate for the filter /** * Filter initialization function. Args contains the user-supplied @@ -176,73 +378,221 @@ typedef struct * 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); - const AVFilterPad *inputs; /// NULL terminated list of inputs. NULL if none - const AVFilterPad *outputs; /// NULL terminated list of outputs. NULL if none + /** + * 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 { - AVClass *av_class; + const AVClass *av_class; ///< needed for av_log() - AVFilter *filter; + AVFilter *filter; ///< the AVFilter of which this is an instance - char *name; + char *name; ///< name of this filter instance - unsigned input_count; - AVFilterPad *input_pads; - AVFilterLink **inputs; + 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; - AVFilterPad *output_pads; - AVFilterLink **outputs; + unsigned output_count; ///< number of output pads + AVFilterPad *output_pads; ///< array of output pads + AVFilterLink **outputs; ///< array of pointers to output links - void *priv; + 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 indices 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; - unsigned int srcpad; + 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 - AVFilterContext *dst; - unsigned int dstpad; + /** 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, h; - enum PixelFormat format; + 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 */ +/** + * 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); -/** Configure the colorspace, dimensions, etc of a link */ -int avfilter_config_link(AVFilterLink *link); +/** + * 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); -void avfilter_request_frame(AVFilterLink *link); + +/** + * 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 imediately available frames + */ +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); -void avfilter_draw_slice(AVFilterLink *link, uint8_t *data[4], int y, int h); -void avfilter_init(void); +/** + * 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); -AVFilter *avfilter_get_by_name(char *name); -AVFilterContext *avfilter_create(AVFilter *filter, char *inst_name); -AVFilterContext *avfilter_create_by_name(char *name, char *inst_name); +/** + * 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); -int *avfilter_make_format_list(int len, ...); +/** + * 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 + * 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