Freeze filter: Fix alpha handling.

diff --git a/src/modules/kdenlive/filter_freeze.c b/src/modules/kdenlive/filter_freeze.c
index 72e4261b6e28f0aa010f40bffd62e40bbba65a64..375205794da54301be3b78de65b8e366ddaf4b9c 100755 (executable)
--- a/src/modules/kdenlive/filter_freeze.c
+++ b/src/modules/kdenlive/filter_freeze.c
@@ -52,7 +52,7 @@ static int filter_get_image( mlt_frame frame, uint8_t **image, mlt_image_format
        if (do_freeze == 1) {
                mlt_service_lock( MLT_FILTER_SERVICE( filter ) );
                freeze_frame = mlt_properties_get_data( properties, "freeze_frame", NULL );
-               if ( freeze_frame == NULL || mlt_properties_get_position( properties, "_frame" ) != pos )
+               if ( !freeze_frame || mlt_properties_get_position( properties, "_frame" ) != pos )
                {
                        // freeze_frame has not been fetched yet or is not useful, so fetch it and cache it.
                        mlt_producer producer = mlt_frame_get_original_producer(frame);
@@ -84,6 +84,12 @@ static int filter_get_image( mlt_frame frame, uint8_t **image, mlt_image_format
                *image = image_copy;
                mlt_frame_set_image( frame, *image, size, mlt_pool_release );
 
+                uint8_t *alpha_buffer = mlt_frame_get_alpha_mask( freeze_frame );
+                int alphasize = *width * *height;
+                uint8_t *alpha_copy = mlt_pool_alloc( alphasize );
+                memcpy( alpha_copy, alpha_buffer, alphasize );
+                mlt_frame_set_alpha( frame, alpha_copy, alphasize, mlt_pool_release );
+
                return error;
        }
 
@@ -121,7 +127,7 @@ mlt_filter filter_freeze_init( mlt_profile profile, mlt_service_type type, const
                // If freeze_after = 1, only frames after the "frame" value will be frozen
                mlt_properties_set( MLT_FILTER_PROPERTIES( filter ), "freeze_after", "0" );
 
-               // If freeze_before = 1, only frames after the "frame" value will be frozen
+               // If freeze_before = 1, only frames before the "frame" value will be frozen
                mlt_properties_set( MLT_FILTER_PROPERTIES( filter ), "freeze_before", "0" );
        }
        return filter;