vf_pad: switch to filter_frame

Based on patch by Anton Khirnov
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavfilter/vf_pad.c

@@ -88,7 +88,6 @@ typedef struct {
     uint8_t rgba_color[4];  ///< color for the padding area
     FFDrawContext draw;
     FFDrawColor color;
-    int needs_copy;
 } PadContext;
 
 static av_cold int init(AVFilterContext *ctx, const char *args)
@@ -263,129 +262,84 @@ static int does_clip(PadContext *pad, AVFilterBufferRef *outpicref, int plane, i
     return 0;
 }
 
-static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
+static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *in)
 {
     PadContext *pad = inlink->dst->priv;
-    AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
-    AVFilterBufferRef *for_next_filter;
-    int plane, ret = 0;
+    AVFilterBufferRef *out = avfilter_ref_buffer(in, ~0);
+    int plane, needs_copy;
 
-    if (!outpicref)
+    if (!out) {
+        avfilter_unref_bufferp(&in);
         return AVERROR(ENOMEM);
+    }
 
-    for (plane = 0; plane < 4 && outpicref->data[plane] && pad->draw.pixelstep[plane]; plane++) {
+    for (plane = 0; plane < 4 && out->data[plane] && pad->draw.pixelstep[plane]; plane++) {
         int hsub = pad->draw.hsub[plane];
         int vsub = pad->draw.vsub[plane];
 
-        av_assert0(outpicref->buf->w>0 && outpicref->buf->h>0);
+        av_assert0(out->buf->w > 0 && out->buf->h > 0);
 
-        if(outpicref->format != outpicref->buf->format) //unsupported currently
+        if (out->format != out->buf->format) //unsupported currently
             break;
 
-        outpicref->data[plane] -=   (pad->x  >> hsub) * pad->draw.pixelstep[plane]
-                                  + (pad->y  >> vsub) * outpicref->linesize[plane];
+        out->data[plane] -= (pad->x  >> hsub) * pad->draw.pixelstep[plane] +
+                            (pad->y  >> vsub) * out->linesize[plane];
 
-        if(   does_clip(pad, outpicref, plane, hsub, vsub, 0, 0)
-           || does_clip(pad, outpicref, plane, hsub, vsub, 0, pad->h-1)
-           || does_clip(pad, outpicref, plane, hsub, vsub, pad->w-1, 0)
-           || does_clip(pad, outpicref, plane, hsub, vsub, pad->w-1, pad->h-1)
-          )
+        if (does_clip(pad, out, plane, hsub, vsub, 0,                   0) ||
+            does_clip(pad, out, plane, hsub, vsub, 0,          pad->h - 1) ||
+            does_clip(pad, out, plane, hsub, vsub, pad->w - 1,          0) ||
+            does_clip(pad, out, plane, hsub, vsub, pad->w - 1, pad->h - 1))
             break;
     }
-    pad->needs_copy= plane < 4 && outpicref->data[plane] || !(outpicref->perms & AV_PERM_WRITE);
-    if(pad->needs_copy){
+    needs_copy = plane < 4 && out->data[plane] || !(out->perms & AV_PERM_WRITE);
+    if (needs_copy) {
         av_log(inlink->dst, AV_LOG_DEBUG, "Direct padding impossible allocating new frame\n");
-        avfilter_unref_buffer(outpicref);
-        outpicref = ff_get_video_buffer(inlink->dst->outputs[0], AV_PERM_WRITE | AV_PERM_NEG_LINESIZES,
-                                        FFMAX(inlink->w, pad->w),
-                                        FFMAX(inlink->h, pad->h));
-        if (!outpicref)
+        avfilter_unref_buffer(out);
+        out = ff_get_video_buffer(inlink->dst->outputs[0], AV_PERM_WRITE | AV_PERM_NEG_LINESIZES,
+                                  FFMAX(inlink->w, pad->w),
+                                  FFMAX(inlink->h, pad->h));
+        if (!out) {
+            avfilter_unref_bufferp(&in);
             return AVERROR(ENOMEM);
+        }
 
-        avfilter_copy_buffer_ref_props(outpicref, inpicref);
+        avfilter_copy_buffer_ref_props(out, in);
     }
 
-    outpicref->video->w = pad->w;
-    outpicref->video->h = pad->h;
-
-    for_next_filter = avfilter_ref_buffer(outpicref, ~0);
-    if (!for_next_filter) {
-        ret = AVERROR(ENOMEM);
-        goto fail;
-    }
-
-    ret = ff_start_frame(inlink->dst->outputs[0], for_next_filter);
-    if (ret < 0)
-        goto fail;
-
-    inlink->dst->outputs[0]->out_buf = outpicref;
-    return 0;
+    out->video->w = pad->w;
+    out->video->h = pad->h;
 
-fail:
-    avfilter_unref_bufferp(&outpicref);
-    return ret;
-}
-
-static int draw_send_bar_slice(AVFilterLink *link, int y, int h, int slice_dir, int before_slice)
-{
-    PadContext *pad = link->dst->priv;
-    int bar_y, bar_h = 0, ret = 0;
-
-    if        (slice_dir * before_slice ==  1 && y == pad->y) {
-        /* top bar */
-        bar_y = 0;
-        bar_h = pad->y;
-    } else if (slice_dir * before_slice == -1 && (y + h) == (pad->y + pad->in_h)) {
-        /* bottom bar */
-        bar_y = pad->y + pad->in_h;
-        bar_h = pad->h - pad->in_h - pad->y;
+    /* top bar */
+    if (pad->y) {
+        ff_fill_rectangle(&pad->draw, &pad->color,
+                          out->data, out->linesize,
+                          0, 0, pad->w, pad->y);
     }
 
-    if (bar_h) {
+    /* bottom bar */
+    if (pad->h > pad->y + pad->in_h) {
         ff_fill_rectangle(&pad->draw, &pad->color,
-                          link->dst->outputs[0]->out_buf->data,
-                          link->dst->outputs[0]->out_buf->linesize,
-                          0, bar_y, pad->w, bar_h);
-        ret = ff_draw_slice(link->dst->outputs[0], bar_y, bar_h, slice_dir);
+                          out->data, out->linesize,
+                          0, pad->y + pad->in_h, pad->w, pad->h - pad->y - pad->in_h);
     }
-    return ret;
-}
-
-static int draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
-{
-    PadContext *pad = link->dst->priv;
-    AVFilterBufferRef *outpic = link->dst->outputs[0]->out_buf;
-    AVFilterBufferRef *inpic = link->cur_buf;
-    int ret;
-
-    y += pad->y;
-
-    y = ff_draw_round_to_sub(&pad->draw, 1, -1, y);
-    h = ff_draw_round_to_sub(&pad->draw, 1, -1, h);
-
-    if (!h)
-        return 0;
-    draw_send_bar_slice(link, y, h, slice_dir, 1);
 
     /* left border */
-    ff_fill_rectangle(&pad->draw, &pad->color, outpic->data, outpic->linesize,
-                      0, y, pad->x, h);
+    ff_fill_rectangle(&pad->draw, &pad->color, out->data, out->linesize,
+                      0, pad->y, pad->x, in->video->h);
 
-    if(pad->needs_copy){
+    if (needs_copy) {
         ff_copy_rectangle2(&pad->draw,
-                           outpic->data, outpic->linesize,
-                           inpic ->data, inpic ->linesize,
-                           pad->x, y, 0, y - pad->y, inpic->video->w, h);
+                          out->data, out->linesize, in->data, in->linesize,
+                          pad->x, pad->y, 0, 0, in->video->w, in->video->h);
     }
 
     /* right border */
-    ff_fill_rectangle(&pad->draw, &pad->color, outpic->data, outpic->linesize,
-                      pad->x + pad->in_w, y, pad->w - pad->x - pad->in_w, h);
-    ret = ff_draw_slice(link->dst->outputs[0], y, h, slice_dir);
-    if (ret < 0)
-        return ret;
+    ff_fill_rectangle(&pad->draw, &pad->color, out->data, out->linesize,
+                      pad->x + pad->in_w, pad->y, pad->w - pad->x - pad->in_w,
+                      in->video->h);
 
-    return draw_send_bar_slice(link, y, h, slice_dir, -1);
+    avfilter_unref_bufferp(&in);
+    return ff_filter_frame(inlink->dst->outputs[0], out);
 }
 
 static const AVFilterPad avfilter_vf_pad_inputs[] = {
@@ -394,8 +348,7 @@ static const AVFilterPad avfilter_vf_pad_inputs[] = {
         .type             = AVMEDIA_TYPE_VIDEO,
         .config_props     = config_input,
         .get_video_buffer = get_video_buffer,
-        .start_frame      = start_frame,
-        .draw_slice       = draw_slice,
+        .filter_frame     = filter_frame,
     },
     { NULL }
 };