lavfi: Add support for increasing hardware frame pool sizes

AVFilterContext.extra_hw_frames functions identically to the field of
the same name in AVCodecContext.

1 files changed, 16 insertions, 0 deletions

diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index 6df69dbbbf..46dbadfcdc 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -311,6 +311,22 @@ struct AVFilterContext {
      * hardware context information.
      */
     AVBufferRef *hw_device_ctx;
+
+    /**
+     * Sets the number of extra hardware frames which the filter will
+     * allocate on its output links for use in following filters or by
+     * the caller.
+     *
+     * Some hardware filters require all frames that they will use for
+     * output to be defined in advance before filtering starts.  For such
+     * filters, any hardware frame pools used for output must therefore be
+     * of fixed size.  The extra frames set here are on top of any number
+     * that the filter needs internally in order to operate normally.
+     *
+     * This field must be set before the graph containing this filter is
+     * configured.
+     */
+    int extra_hw_frames;
 };
 
 /**