| /* |
| * Filters implementation helper functions |
| * |
| * 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_FILTERS_H |
| #define AVFILTER_FILTERS_H |
| |
| /** |
| * Filters implementation helper functions |
| */ |
| |
| #include "avfilter.h" |
| |
| /** |
| * Mark a filter ready and schedule it for activation. |
| * |
| * This is automatically done when something happens to the filter (queued |
| * frame, status change, request on output). |
| * Filters implementing the activate callback can call it directly to |
| * perform one more round of processing later. |
| * It is also useful for filters reacting to external or asynchronous |
| * events. |
| */ |
| void ff_filter_set_ready(AVFilterContext *filter, unsigned priority); |
| |
| /** |
| * Process the commands queued in the link up to the time of the frame. |
| * Commands will trigger the process_command() callback. |
| * @return >= 0 or AVERROR code. |
| */ |
| int ff_inlink_process_commands(AVFilterLink *link, const AVFrame *frame); |
| |
| /** |
| * Evaluate the timeline expression of the link for the time and properties |
| * of the frame. |
| * @return >0 if enabled, 0 if disabled |
| * @note It does not update link->dst->is_disabled. |
| */ |
| int ff_inlink_evaluate_timeline_at_frame(AVFilterLink *link, const AVFrame *frame); |
| |
| /** |
| * Test if a frame is available on the link. |
| * @return >0 if a frame is available |
| */ |
| int ff_inlink_check_available_frame(AVFilterLink *link); |
| |
| /** |
| * Test if enough samples are available on the link. |
| * @return >0 if enough samples are available |
| * @note on EOF and error, min becomes 1 |
| */ |
| int ff_inlink_check_available_samples(AVFilterLink *link, unsigned min); |
| |
| /** |
| * Take a frame from the link's FIFO and update the link's stats. |
| * |
| * If ff_inlink_check_available_frame() was previously called, the |
| * preferred way of expressing it is "av_assert1(ret);" immediately after |
| * ff_inlink_consume_frame(). Negative error codes must still be checked. |
| * |
| * @note May trigger process_command() and/or update is_disabled. |
| * @return >0 if a frame is available, |
| * 0 and set rframe to NULL if no frame available, |
| * or AVERROR code |
| */ |
| int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe); |
| |
| /** |
| * Take samples from the link's FIFO and update the link's stats. |
| * |
| * If ff_inlink_check_available_samples() was previously called, the |
| * preferred way of expressing it is "av_assert1(ret);" immediately after |
| * ff_inlink_consume_samples(). Negative error codes must still be checked. |
| * |
| * @note May trigger process_command() and/or update is_disabled. |
| * @return >0 if a frame is available, |
| * 0 and set rframe to NULL if no frame available, |
| * or AVERROR code |
| */ |
| int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max, |
| AVFrame **rframe); |
| |
| /** |
| * Make sure a frame is writable. |
| * This is similar to av_frame_make_writable() except it uses the link's |
| * buffer allocation callback, and therefore allows direct rendering. |
| */ |
| int ff_inlink_make_frame_writable(AVFilterLink *link, AVFrame **rframe); |
| |
| /** |
| * Test and acknowledge the change of status on the link. |
| * |
| * Status means EOF or an error condition; a change from the normal (0) |
| * status to a non-zero status can be queued in a filter's input link, it |
| * becomes relevant after the frames queued in the link's FIFO are |
| * processed. This function tests if frames are still queued and if a queued |
| * status change has not yet been processed. In that case it performs basic |
| * treatment (updating the link's timestamp) and returns a positive value to |
| * let the filter do its own treatments (flushing...). |
| * |
| * Filters implementing the activate callback should call this function when |
| * they think it might succeed (usually after checking unsuccessfully for a |
| * queued frame). |
| * Filters implementing the filter_frame and request_frame callbacks do not |
| * need to call that since the same treatment happens in ff_filter_frame(). |
| * |
| * @param[out] rstatus new or current status |
| * @param[out] rpts current timestamp of the link in link time base |
| * @return >0 if status changed, <0 if status already acked, 0 otherwise |
| */ |
| int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts); |
| |
| /** |
| * Mark that a frame is wanted on the link. |
| * Unlike ff_filter_frame(), it must not be called when the link has a |
| * non-zero status, and thus does not acknowledge it. |
| * Also it cannot fail. |
| */ |
| void ff_inlink_request_frame(AVFilterLink *link); |
| |
| #endif /* AVFILTER_FILTERS_H */ |