Set the alpha channel size more reliably in imageconvert.

diff --git a/src/modules/core/filter_imageconvert.c b/src/modules/core/filter_imageconvert.c
index 41567235bd0d743163dcd3134013de0930bbc6aa..99378604b1658a062a915bc7d81476abc49f0b27 100644 (file)
--- a/src/modules/core/filter_imageconvert.c
+++ b/src/modules/core/filter_imageconvert.c
@@ -329,18 +329,22 @@ static int convert_image( mlt_frame frame, uint8_t **buffer, mlt_image_format *f
                if ( converter )
                {
                        int size = width * height * bpp_table[ requested_format - 1 ];
+                       int alpha_size = width * height;
                        uint8_t *image = mlt_pool_alloc( size );
                        uint8_t *alpha = ( *format == mlt_image_rgb24a ||
                                           *format == mlt_image_opengl )
                                         ? mlt_pool_alloc( width * height ) : NULL;
                        if ( requested_format == mlt_image_rgb24a || requested_format == mlt_image_opengl )
+                       {
                                alpha = mlt_frame_get_alpha_mask( frame );
+                               mlt_properties_get_data( properties, "alpha", &alpha_size );
+                       }
 
                        if ( !( error = converter( *buffer, image, alpha, width, height ) ) )
                        {
                                mlt_properties_set_data( properties, "image", image, size, mlt_pool_release, NULL );
                                if ( alpha && ( *format == mlt_image_rgb24a || *format == mlt_image_opengl ) )
-                                       mlt_properties_set_data( properties, "alpha", alpha, width * height, mlt_pool_release, NULL );
+                                       mlt_properties_set_data( properties, "alpha", alpha, alpha_size, mlt_pool_release, NULL );
                                *buffer = image;
                                *format = requested_format;
                        }