Move default entry point implementations to their own file.

Make them externally visible because they may be useful for filters to use.

Commited in SoC by Bobby Bingham on 2007-08-02 15:14:05

Originally committed as revision 12063 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavfilter/defaults.c

+/*
+ * Filter layer - default implementations
+ * 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
+ */
+
+#include "avfilter.h"
+
+/* TODO: buffer pool.  see comment for avfilter_default_get_video_buffer() */
+void avfilter_default_free_video_buffer(AVFilterPic *pic)
+{
+    avpicture_free((AVPicture *) pic);
+    av_free(pic);
+}
+
+/* TODO: set the buffer's priv member to a context structure for the whole
+ * filter chain.  This will allow for a buffer pool instead of the constant
+ * alloc & free cycle currently implemented. */
+AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link, int perms)
+{
+    AVFilterPic *pic = av_mallocz(sizeof(AVFilterPic));
+    AVFilterPicRef *ref = av_mallocz(sizeof(AVFilterPicRef));
+
+    ref->pic   = pic;
+    ref->w     = link->w;
+    ref->h     = link->h;
+    ref->perms = perms;
+
+    pic->refcount = 1;
+    pic->format   = link->format;
+    pic->free     = avfilter_default_free_video_buffer;
+    avpicture_alloc((AVPicture *)pic, pic->format, ref->w, ref->h);
+
+    memcpy(ref->data,     pic->data,     sizeof(pic->data));
+    memcpy(ref->linesize, pic->linesize, sizeof(pic->linesize));
+
+    return ref;
+}
+
+void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
+{
+    AVFilterLink *out = NULL;
+
+    if(link->dst->output_count)
+        out = link->dst->outputs[0];
+
+    link->cur_pic = picref;
+
+    if(out) {
+        out->outpic      = avfilter_get_video_buffer(out, AV_PERM_WRITE);
+        out->outpic->pts = picref->pts;
+        avfilter_start_frame(out, avfilter_ref_pic(out->outpic, ~0));
+    }
+}
+
+void avfilter_default_end_frame(AVFilterLink *link)
+{
+    AVFilterLink *out = NULL;
+
+    if(link->dst->output_count)
+        out = link->dst->outputs[0];
+
+    avfilter_unref_pic(link->cur_pic);
+    link->cur_pic = NULL;
+
+    if(out) {
+        avfilter_unref_pic(out->outpic);
+        out->outpic = NULL;
+        avfilter_end_frame(out);
+    }
+}
+
+/**
+ * default config_link() implementation for output video links to simplify
+ * the implementation of one input one output video filters */
+int avfilter_default_config_output_link(AVFilterLink *link)
+{
+    if(link->src->input_count && link->src->inputs[0]) {
+        link->w = link->src->inputs[0]->w;
+        link->h = link->src->inputs[0]->h;
+    } else {
+        /* XXX: any non-simple filter which would cause this branch to be taken
+         * really should implement its own config_props() for this link. */
+        link->w =
+        link->h = 0;
+    }
+
+    return 0;
+}
+
+/**
+ * default query_formats() implementation for output video links to simplify
+ * the implementation of one input one output video filters */
+int *avfilter_default_query_output_formats(AVFilterLink *link)
+{
+    if(link->src->input_count && link->src->inputs[0])
+        return avfilter_make_format_list(1, link->src->inputs[0]->format);
+    else
+        /* XXX: any non-simple filter which would cause this branch to be taken
+         * really should implement its own query_formats() for this link */
+        return avfilter_make_format_list(0);
+}
+