avfilter/vsrc_ddagrab: only use buffer texture if parameters actually…

… mismatch

libavfilter/vsrc_ddagrab.c

@@ -709,29 +709,9 @@ static int next_frame_internal(AVFilterContext *avctx, ID3D11Texture2D **desktop
             goto error;
     }
 
-    if (!frame_info.LastPresentTime.QuadPart || !frame_info.AccumulatedFrames) {
-        if (need_frame) {
-            ret = AVERROR(EAGAIN);
-            goto error;
-        }
-
-        // Unforunately, we can't rely on the desktop_resource's format in this case.
-        // The API might even return it in with a format that was not in the initial
-        // list of supported formats, and it can change/flicker randomly.
-        // To work around this, return an internal copy of the last valid texture we got.
-        release_resource(&desktop_resource);
-
-        // The initial probing should make this impossible.
-        if (!dda->buffer_texture) {
-            av_log(avctx, AV_LOG_ERROR, "No buffer texture while operating!\n");
-            ret = AVERROR_BUG;
-            goto error;
-        }
-
-        av_log(avctx, AV_LOG_TRACE, "Returning internal buffer for a frame!\n");
-        ID3D11Texture2D_AddRef(dda->buffer_texture);
-        *desktop_texture = dda->buffer_texture;
-        return 0;
+    if (need_frame && (!frame_info.LastPresentTime.QuadPart || !frame_info.AccumulatedFrames)) {
+        ret = AVERROR(EAGAIN);
+        goto error;
     }
 
     hr = IDXGIResource_QueryInterface(desktop_resource, &IID_ID3D11Texture2D, (void**)desktop_texture);
@@ -1147,10 +1127,12 @@ static int ddagrab_request_frame(AVFilterLink *outlink)
     ID3D11Texture2D_GetDesc(cur_texture, &desc);
     if (desc.Format != dda->raw_format ||
         (int)desc.Width != dda->raw_width ||
-        (int)desc.Height != dda->raw_height) {
-        av_log(avctx, AV_LOG_ERROR, "Output parameters changed!\n");
-        ret = AVERROR_OUTPUT_CHANGED;
-        goto fail;
+        (int)desc.Height != dda->raw_height)
+    {
+        av_log(avctx, AV_LOG_DEBUG, "Output parameters changed, falling back to buffer.\n");
+        release_resource(&cur_texture);
+        ID3D11Texture2D_AddRef(dda->buffer_texture);
+        cur_texture = dda->buffer_texture;
     }
 
     frame = ff_get_video_buffer(outlink, dda->width, dda->height);