libavfilter/video.c - third_party/ffmpeg - Git at Google

 /*
  * Copyright 2007 Bobby Bingham
  * Copyright Stefano Sabatini <stefasab gmail com>
  * Copyright Vitor Sessak <vitor1001 gmail com>
  *
  * 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
  */

 #include "libavutil/imgutils.h"

 #include "avfilter.h"
 #include "internal.h"
 #include "video.h"

 static char *ff_get_ref_perms_string(char *buf, size_t buf_size, int perms)
 {
     snprintf(buf, buf_size, "%s%s%s%s%s%s",
              perms & AV_PERM_READ      ? "r" : "",
              perms & AV_PERM_WRITE     ? "w" : "",
              perms & AV_PERM_PRESERVE  ? "p" : "",
              perms & AV_PERM_REUSE     ? "u" : "",
              perms & AV_PERM_REUSE2    ? "U" : "",
              perms & AV_PERM_NEG_LINESIZES ? "n" : "");
     return buf;
 }

 static void ff_dlog_ref(void *ctx, AVFilterBufferRef *ref, int end)
 {
     av_unused char buf[16];
     av_dlog(ctx,
             "ref[%p buf:%p refcount:%d perms:%s data:%p linesize[%d, %d, %d, %d] pts:%"PRId64" pos:%"PRId64,
             ref, ref->buf, ref->buf->refcount, ff_get_ref_perms_string(buf, sizeof(buf), ref->perms), ref->data[0],
             ref->linesize[0], ref->linesize[1], ref->linesize[2], ref->linesize[3],
             ref->pts, ref->pos);

     if (ref->video) {
         av_dlog(ctx, " a:%d/%d s:%dx%d i:%c iskey:%d type:%c",
                 ref->video->sample_aspect_ratio.num, ref->video->sample_aspect_ratio.den,
                 ref->video->w, ref->video->h,
                 !ref->video->interlaced     ? 'P' :         /* Progressive  */
                 ref->video->top_field_first ? 'T' : 'B',    /* Top / Bottom */
                 ref->video->key_frame,
                 av_get_picture_type_char(ref->video->pict_type));
     }
     if (ref->audio) {
         av_dlog(ctx, " cl:%"PRId64"d n:%d r:%d",
                 ref->audio->channel_layout,
                 ref->audio->nb_samples,
                 ref->audio->sample_rate);
     }

     av_dlog(ctx, "]%s", end ? "\n" : "");
 }

 AVFilterBufferRef *ff_null_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
 {
     return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
 }

 AVFilterBufferRef *ff_default_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
 {
     int linesize[4];
     uint8_t *data[4];
     int i;
     AVFilterBufferRef *picref = NULL;
     AVFilterPool *pool = link->pool;

     if (pool) {
         for (i = 0; i < POOL_SIZE; i++) {
             picref = pool->pic[i];
             if (picref && picref->buf->format == link->format && picref->buf->w == w && picref->buf->h == h) {
                 AVFilterBuffer *pic = picref->buf;
                 pool->pic[i] = NULL;
                 pool->count--;
                 picref->video->w = w;
                 picref->video->h = h;
                 picref->perms = perms | AV_PERM_READ;
                 picref->format = link->format;
                 pic->refcount = 1;
                 memcpy(picref->data,     pic->data,     sizeof(picref->data));
                 memcpy(picref->linesize, pic->linesize, sizeof(picref->linesize));
                 pool->refcount++;
                 return picref;
             }
         }
     } else {
         pool = link->pool = av_mallocz(sizeof(AVFilterPool));
         pool->refcount = 1;
     }

     // align: +2 is needed for swscaler, +16 to be SIMD-friendly
     if ((i = av_image_alloc(data, linesize, w, h, link->format, 32)) < 0)
         return NULL;

     picref = avfilter_get_video_buffer_ref_from_arrays(data, linesize,
                                                        perms, w, h, link->format);
     if (!picref) {
         av_free(data[0]);
         return NULL;
     }

     memset(data[0], 128, i);

     picref->buf->priv = pool;
     picref->buf->free = NULL;
     pool->refcount++;

     return picref;
 }

 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)
 {
     AVFilterBuffer *pic = av_mallocz(sizeof(AVFilterBuffer));
     AVFilterBufferRef *picref = av_mallocz(sizeof(AVFilterBufferRef));

     if (!pic || !picref)
         goto fail;

     picref->buf = pic;
     picref->buf->free = ff_avfilter_default_free_buffer;
     if (!(picref->video = av_mallocz(sizeof(AVFilterBufferRefVideoProps))))
         goto fail;

     pic->w = picref->video->w = w;
     pic->h = picref->video->h = h;

     /* make sure the buffer gets read permission or it's useless for output */
     picref->perms = perms | AV_PERM_READ;

     pic->refcount = 1;
     picref->type = AVMEDIA_TYPE_VIDEO;
     pic->format = picref->format = format;

     memcpy(pic->data,        data,          4*sizeof(data[0]));
     memcpy(pic->linesize,    linesize,      4*sizeof(linesize[0]));
     memcpy(picref->data,     pic->data,     sizeof(picref->data));
     memcpy(picref->linesize, pic->linesize, sizeof(picref->linesize));

     pic->   extended_data = pic->data;
     picref->extended_data = picref->data;

     picref->pts = AV_NOPTS_VALUE;

     return picref;

 fail:
     if (picref && picref->video)
         av_free(picref->video);
     av_free(picref);
     av_free(pic);
     return NULL;
 }

 AVFilterBufferRef *avfilter_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
 {
     AVFilterBufferRef *ret = NULL;

     av_unused char buf[16];
     FF_DPRINTF_START(NULL, get_video_buffer); ff_dlog_link(NULL, link, 0);
     av_dlog(NULL, " perms:%s w:%d h:%d\n", ff_get_ref_perms_string(buf, sizeof(buf), perms), w, h);

     if (link->dstpad->get_video_buffer)
         ret = link->dstpad->get_video_buffer(link, perms, w, h);

     if (!ret)
         ret = ff_default_get_video_buffer(link, perms, w, h);

     if (ret)
         ret->type = AVMEDIA_TYPE_VIDEO;

     FF_DPRINTF_START(NULL, get_video_buffer); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " returning "); ff_dlog_ref(NULL, ret, 1);

     return ret;
 }

 void ff_null_start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
 {
     avfilter_start_frame(link->dst->outputs[0], picref);
 }

 static void default_start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
 {
     AVFilterLink *outlink = NULL;

     if (inlink->dst->output_count)
         outlink = inlink->dst->outputs[0];

     if (outlink) {
         outlink->out_buf = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
         avfilter_copy_buffer_ref_props(outlink->out_buf, picref);
         avfilter_start_frame(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));
     }
 }

 /* XXX: should we do the duplicating of the picture ref here, instead of
  * forcing the source filter to do it? */
 void avfilter_start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
 {
     void (*start_frame)(AVFilterLink *, AVFilterBufferRef *);
     AVFilterPad *dst = link->dstpad;
     int perms = picref->perms;
     AVFilterCommand *cmd= link->dst->command_queue;

     FF_DPRINTF_START(NULL, start_frame); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " "); ff_dlog_ref(NULL, picref, 1);

     if (!(start_frame = dst->start_frame))
         start_frame = default_start_frame;

     if (picref->linesize[0] < 0)
         perms |= AV_PERM_NEG_LINESIZES;
     /* prepare to copy the picture if it has insufficient permissions */
     if ((dst->min_perms & perms) != dst->min_perms || dst->rej_perms & perms) {
         av_log(link->dst, AV_LOG_DEBUG,
                 "frame copy needed (have perms %x, need %x, reject %x)\n",
                 picref->perms,
                 link->dstpad->min_perms, link->dstpad->rej_perms);

         link->cur_buf = avfilter_get_video_buffer(link, dst->min_perms, link->w, link->h);
         link->src_buf = picref;
         avfilter_copy_buffer_ref_props(link->cur_buf, link->src_buf);

         /* copy palette if required */
         if (av_pix_fmt_descriptors[link->format].flags & PIX_FMT_PAL)
             memcpy(link->cur_buf->data[1], link->src_buf-> data[1], AVPALETTE_SIZE);
     }
     else
         link->cur_buf = picref;

     while(cmd && cmd->time <= picref->pts * av_q2d(link->time_base)){
         av_log(link->dst, AV_LOG_DEBUG,
                "Processing command time:%f command:%s arg:%s\n",
                cmd->time, cmd->command, cmd->arg);
         avfilter_process_command(link->dst, cmd->command, cmd->arg, 0, 0, cmd->flags);
         ff_command_queue_pop(link->dst);
         cmd= link->dst->command_queue;
     }

     start_frame(link, link->cur_buf);
     ff_update_link_current_pts(link, link->cur_buf->pts);
 }

 void ff_null_end_frame(AVFilterLink *link)
 {
     avfilter_end_frame(link->dst->outputs[0]);
 }

 static void default_end_frame(AVFilterLink *inlink)
 {
     AVFilterLink *outlink = NULL;

     if (inlink->dst->output_count)
         outlink = inlink->dst->outputs[0];

     avfilter_unref_buffer(inlink->cur_buf);
     inlink->cur_buf = NULL;

     if (outlink) {
         if (outlink->out_buf) {
             avfilter_unref_buffer(outlink->out_buf);
             outlink->out_buf = NULL;
         }
         avfilter_end_frame(outlink);
     }
 }

 void avfilter_end_frame(AVFilterLink *link)
 {
     void (*end_frame)(AVFilterLink *);

     if (!(end_frame = link->dstpad->end_frame))
         end_frame = default_end_frame;

     end_frame(link);

     /* unreference the source picture if we're feeding the destination filter
      * a copied version dues to permission issues */
     if (link->src_buf) {
         avfilter_unref_buffer(link->src_buf);
         link->src_buf = NULL;
     }
 }

 void ff_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
 {
     avfilter_draw_slice(link->dst->outputs[0], y, h, slice_dir);
 }

 static void default_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
 {
     AVFilterLink *outlink = NULL;

     if (inlink->dst->output_count)
         outlink = inlink->dst->outputs[0];

     if (outlink)
         avfilter_draw_slice(outlink, y, h, slice_dir);
 }

 void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
 {
     uint8_t *src[4], *dst[4];
     int i, j, vsub;
     void (*draw_slice)(AVFilterLink *, int, int, int);

     FF_DPRINTF_START(NULL, draw_slice); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " y:%d h:%d dir:%d\n", y, h, slice_dir);

     /* copy the slice if needed for permission reasons */
     if (link->src_buf) {
         vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h;

         for (i = 0; i < 4; i++) {
             if (link->src_buf->data[i]) {
                 src[i] = link->src_buf-> data[i] +
                     (y >> (i==1 || i==2 ? vsub : 0)) * link->src_buf-> linesize[i];
                 dst[i] = link->cur_buf->data[i] +
                     (y >> (i==1 || i==2 ? vsub : 0)) * link->cur_buf->linesize[i];
             } else
                 src[i] = dst[i] = NULL;
         }

         for (i = 0; i < 4; i++) {
             int planew =
                 av_image_get_linesize(link->format, link->cur_buf->video->w, i);

             if (!src[i]) continue;

             for (j = 0; j < h >> (i==1 || i==2 ? vsub : 0); j++) {
                 memcpy(dst[i], src[i], planew);
                 src[i] += link->src_buf->linesize[i];
                 dst[i] += link->cur_buf->linesize[i];
             }
         }
     }

     if (!(draw_slice = link->dstpad->draw_slice))
         draw_slice = default_draw_slice;
     draw_slice(link, y, h, slice_dir);
 }

 #if FF_API_FILTERS_PUBLIC
 AVFilterBufferRef *avfilter_default_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
 {
     return ff_default_get_video_buffer(link, perms, w, h);
 }
 void avfilter_default_start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
 {
     default_start_frame(inlink, picref);
 }
 void avfilter_default_end_frame(AVFilterLink *inlink)
 {
     default_end_frame(inlink);
 }
 void avfilter_default_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
 {
     default_draw_slice(inlink, y, h, slice_dir);
 }
 AVFilterBufferRef *avfilter_null_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
 {
     return ff_null_get_video_buffer(link, perms, w, h);
 }
 void avfilter_null_start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
 {
     ff_null_start_frame(link, picref);
 }
 void avfilter_null_end_frame(AVFilterLink *link)
 {
     ff_null_end_frame(link);
 }
 void avfilter_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
 {
     ff_null_draw_slice(link, y, h, slice_dir);
 }
 #endif
	/*
	* Copyright 2007 Bobby Bingham
	* Copyright Stefano Sabatini <stefasab gmail com>
	* Copyright Vitor Sessak <vitor1001 gmail com>
	*
	* 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
	*/

	#include "libavutil/imgutils.h"

	#include "avfilter.h"
	#include "internal.h"
	#include "video.h"

	static char ff_get_ref_perms_string(char buf, size_t buf_size, int perms)
	{
	snprintf(buf, buf_size, "%s%s%s%s%s%s",
	perms & AV_PERM_READ ? "r" : "",
	perms & AV_PERM_WRITE ? "w" : "",
	perms & AV_PERM_PRESERVE ? "p" : "",
	perms & AV_PERM_REUSE ? "u" : "",
	perms & AV_PERM_REUSE2 ? "U" : "",
	perms & AV_PERM_NEG_LINESIZES ? "n" : "");
	return buf;
	}

	static void ff_dlog_ref(void ctx, AVFilterBufferRef ref, int end)
	{
	av_unused char buf[16];
	av_dlog(ctx,
	"ref[%p buf:%p refcount:%d perms:%s data:%p linesize[%d, %d, %d, %d] pts:%"PRId64" pos:%"PRId64,
	ref, ref->buf, ref->buf->refcount, ff_get_ref_perms_string(buf, sizeof(buf), ref->perms), ref->data[0],
	ref->linesize[0], ref->linesize[1], ref->linesize[2], ref->linesize[3],
	ref->pts, ref->pos);

	if (ref->video) {
	av_dlog(ctx, " a:%d/%d s:%dx%d i:%c iskey:%d type:%c",
	ref->video->sample_aspect_ratio.num, ref->video->sample_aspect_ratio.den,
	ref->video->w, ref->video->h,
	!ref->video->interlaced ? 'P' : /* Progressive */
	ref->video->top_field_first ? 'T' : 'B', /* Top / Bottom */
	ref->video->key_frame,
	av_get_picture_type_char(ref->video->pict_type));
	}
	if (ref->audio) {
	av_dlog(ctx, " cl:%"PRId64"d n:%d r:%d",
	ref->audio->channel_layout,
	ref->audio->nb_samples,
	ref->audio->sample_rate);
	}

	av_dlog(ctx, "]%s", end ? "\n" : "");
	}

	AVFilterBufferRef ff_null_get_video_buffer(AVFilterLink link, int perms, int w, int h)
	{
	return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
	}

	AVFilterBufferRef ff_default_get_video_buffer(AVFilterLink link, int perms, int w, int h)
	{
	int linesize[4];
	uint8_t *data[4];
	int i;
	AVFilterBufferRef *picref = NULL;
	AVFilterPool *pool = link->pool;

	if (pool) {
	for (i = 0; i < POOL_SIZE; i++) {
	picref = pool->pic[i];
	if (picref && picref->buf->format == link->format && picref->buf->w == w && picref->buf->h == h) {
	AVFilterBuffer *pic = picref->buf;
	pool->pic[i] = NULL;
	pool->count--;
	picref->video->w = w;
	picref->video->h = h;
	picref->perms = perms \| AV_PERM_READ;
	picref->format = link->format;
	pic->refcount = 1;
	memcpy(picref->data, pic->data, sizeof(picref->data));
	memcpy(picref->linesize, pic->linesize, sizeof(picref->linesize));
	pool->refcount++;
	return picref;
	}
	}
	} else {
	pool = link->pool = av_mallocz(sizeof(AVFilterPool));
	pool->refcount = 1;
	}

	// align: +2 is needed for swscaler, +16 to be SIMD-friendly
	if ((i = av_image_alloc(data, linesize, w, h, link->format, 32)) < 0)
	return NULL;

	picref = avfilter_get_video_buffer_ref_from_arrays(data, linesize,
	perms, w, h, link->format);
	if (!picref) {
	av_free(data[0]);
	return NULL;
	}

	memset(data[0], 128, i);

	picref->buf->priv = pool;
	picref->buf->free = NULL;
	pool->refcount++;

	return picref;
	}

	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)
	{
	AVFilterBuffer *pic = av_mallocz(sizeof(AVFilterBuffer));
	AVFilterBufferRef *picref = av_mallocz(sizeof(AVFilterBufferRef));

	if (!pic \|\| !picref)
	goto fail;

	picref->buf = pic;
	picref->buf->free = ff_avfilter_default_free_buffer;
	if (!(picref->video = av_mallocz(sizeof(AVFilterBufferRefVideoProps))))
	goto fail;

	pic->w = picref->video->w = w;
	pic->h = picref->video->h = h;

	/* make sure the buffer gets read permission or it's useless for output */
	picref->perms = perms \| AV_PERM_READ;

	pic->refcount = 1;
	picref->type = AVMEDIA_TYPE_VIDEO;
	pic->format = picref->format = format;

	memcpy(pic->data, data, 4*sizeof(data[0]));
	memcpy(pic->linesize, linesize, 4*sizeof(linesize[0]));
	memcpy(picref->data, pic->data, sizeof(picref->data));
	memcpy(picref->linesize, pic->linesize, sizeof(picref->linesize));

	pic-> extended_data = pic->data;
	picref->extended_data = picref->data;

	picref->pts = AV_NOPTS_VALUE;

	return picref;

	fail:
	if (picref && picref->video)
	av_free(picref->video);
	av_free(picref);
	av_free(pic);
	return NULL;
	}

	AVFilterBufferRef avfilter_get_video_buffer(AVFilterLink link, int perms, int w, int h)
	{
	AVFilterBufferRef *ret = NULL;

	av_unused char buf[16];
	FF_DPRINTF_START(NULL, get_video_buffer); ff_dlog_link(NULL, link, 0);
	av_dlog(NULL, " perms:%s w:%d h:%d\n", ff_get_ref_perms_string(buf, sizeof(buf), perms), w, h);

	if (link->dstpad->get_video_buffer)
	ret = link->dstpad->get_video_buffer(link, perms, w, h);

	if (!ret)
	ret = ff_default_get_video_buffer(link, perms, w, h);

	if (ret)
	ret->type = AVMEDIA_TYPE_VIDEO;

	FF_DPRINTF_START(NULL, get_video_buffer); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " returning "); ff_dlog_ref(NULL, ret, 1);

	return ret;
	}

	void ff_null_start_frame(AVFilterLink link, AVFilterBufferRef picref)
	{
	avfilter_start_frame(link->dst->outputs[0], picref);
	}

	static void default_start_frame(AVFilterLink inlink, AVFilterBufferRef picref)
	{
	AVFilterLink *outlink = NULL;

	if (inlink->dst->output_count)
	outlink = inlink->dst->outputs[0];

	if (outlink) {
	outlink->out_buf = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
	avfilter_copy_buffer_ref_props(outlink->out_buf, picref);
	avfilter_start_frame(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));
	}
	}

	/* XXX: should we do the duplicating of the picture ref here, instead of
	* forcing the source filter to do it? */
	void avfilter_start_frame(AVFilterLink link, AVFilterBufferRef picref)
	{
	void (start_frame)(AVFilterLink , AVFilterBufferRef *);
	AVFilterPad *dst = link->dstpad;
	int perms = picref->perms;
	AVFilterCommand *cmd= link->dst->command_queue;

	FF_DPRINTF_START(NULL, start_frame); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " "); ff_dlog_ref(NULL, picref, 1);

	if (!(start_frame = dst->start_frame))
	start_frame = default_start_frame;

	if (picref->linesize[0] < 0)
	perms \|= AV_PERM_NEG_LINESIZES;
	/* prepare to copy the picture if it has insufficient permissions */
	if ((dst->min_perms & perms) != dst->min_perms \|\| dst->rej_perms & perms) {
	av_log(link->dst, AV_LOG_DEBUG,
	"frame copy needed (have perms %x, need %x, reject %x)\n",
	picref->perms,
	link->dstpad->min_perms, link->dstpad->rej_perms);

	link->cur_buf = avfilter_get_video_buffer(link, dst->min_perms, link->w, link->h);
	link->src_buf = picref;
	avfilter_copy_buffer_ref_props(link->cur_buf, link->src_buf);

	/* copy palette if required */
	if (av_pix_fmt_descriptors[link->format].flags & PIX_FMT_PAL)
	memcpy(link->cur_buf->data[1], link->src_buf-> data[1], AVPALETTE_SIZE);
	}
	else
	link->cur_buf = picref;

	while(cmd && cmd->time <= picref->pts * av_q2d(link->time_base)){
	av_log(link->dst, AV_LOG_DEBUG,
	"Processing command time:%f command:%s arg:%s\n",
	cmd->time, cmd->command, cmd->arg);
	avfilter_process_command(link->dst, cmd->command, cmd->arg, 0, 0, cmd->flags);
	ff_command_queue_pop(link->dst);
	cmd= link->dst->command_queue;
	}

	start_frame(link, link->cur_buf);
	ff_update_link_current_pts(link, link->cur_buf->pts);
	}

	void ff_null_end_frame(AVFilterLink *link)
	{
	avfilter_end_frame(link->dst->outputs[0]);
	}

	static void default_end_frame(AVFilterLink *inlink)
	{
	AVFilterLink *outlink = NULL;

	if (inlink->dst->output_count)
	outlink = inlink->dst->outputs[0];

	avfilter_unref_buffer(inlink->cur_buf);
	inlink->cur_buf = NULL;

	if (outlink) {
	if (outlink->out_buf) {
	avfilter_unref_buffer(outlink->out_buf);
	outlink->out_buf = NULL;
	}
	avfilter_end_frame(outlink);
	}
	}

	void avfilter_end_frame(AVFilterLink *link)
	{
	void (end_frame)(AVFilterLink );

	if (!(end_frame = link->dstpad->end_frame))
	end_frame = default_end_frame;

	end_frame(link);

	/* unreference the source picture if we're feeding the destination filter
	* a copied version dues to permission issues */
	if (link->src_buf) {
	avfilter_unref_buffer(link->src_buf);
	link->src_buf = NULL;
	}
	}

	void ff_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
	{
	avfilter_draw_slice(link->dst->outputs[0], y, h, slice_dir);
	}

	static void default_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
	{
	AVFilterLink *outlink = NULL;

	if (inlink->dst->output_count)
	outlink = inlink->dst->outputs[0];

	if (outlink)
	avfilter_draw_slice(outlink, y, h, slice_dir);
	}

	void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
	{
	uint8_t src[4], dst[4];
	int i, j, vsub;
	void (draw_slice)(AVFilterLink , int, int, int);

	FF_DPRINTF_START(NULL, draw_slice); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " y:%d h:%d dir:%d\n", y, h, slice_dir);

	/* copy the slice if needed for permission reasons */
	if (link->src_buf) {
	vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h;

	for (i = 0; i < 4; i++) {
	if (link->src_buf->data[i]) {
	src[i] = link->src_buf-> data[i] +
	(y >> (i==1 \|\| i==2 ? vsub : 0)) * link->src_buf-> linesize[i];
	dst[i] = link->cur_buf->data[i] +
	(y >> (i==1 \|\| i==2 ? vsub : 0)) * link->cur_buf->linesize[i];
	} else
	src[i] = dst[i] = NULL;
	}

	for (i = 0; i < 4; i++) {
	int planew =
	av_image_get_linesize(link->format, link->cur_buf->video->w, i);

	if (!src[i]) continue;

	for (j = 0; j < h >> (i==1 \|\| i==2 ? vsub : 0); j++) {
	memcpy(dst[i], src[i], planew);
	src[i] += link->src_buf->linesize[i];
	dst[i] += link->cur_buf->linesize[i];
	}
	}
	}

	if (!(draw_slice = link->dstpad->draw_slice))
	draw_slice = default_draw_slice;
	draw_slice(link, y, h, slice_dir);
	}

	#if FF_API_FILTERS_PUBLIC
	AVFilterBufferRef avfilter_default_get_video_buffer(AVFilterLink link, int perms, int w, int h)
	{
	return ff_default_get_video_buffer(link, perms, w, h);
	}
	void avfilter_default_start_frame(AVFilterLink inlink, AVFilterBufferRef picref)
	{
	default_start_frame(inlink, picref);
	}
	void avfilter_default_end_frame(AVFilterLink *inlink)
	{
	default_end_frame(inlink);
	}
	void avfilter_default_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
	{
	default_draw_slice(inlink, y, h, slice_dir);
	}
	AVFilterBufferRef avfilter_null_get_video_buffer(AVFilterLink link, int perms, int w, int h)
	{
	return ff_null_get_video_buffer(link, perms, w, h);
	}
	void avfilter_null_start_frame(AVFilterLink link, AVFilterBufferRef picref)
	{
	ff_null_start_frame(link, picref);
	}
	void avfilter_null_end_frame(AVFilterLink *link)
	{
	ff_null_end_frame(link);
	}
	void avfilter_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
	{
	ff_null_draw_slice(link, y, h, slice_dir);
	}
	#endif