+ Big endian patch courtesy of Goncalo Carvalho (glslang at gmail dot com) - specific...

[melted] / src / modules / avformat / filter_avcolour_space.c

diff --git a/src/modules/avformat/filter_avcolour_space.c b/src/modules/avformat/filter_avcolour_space.c
index 50eb2ce..9ea2b8f 100644 (file)
--- a/src/modules/avformat/filter_avcolour_space.c
+++ b/src/modules/avformat/filter_avcolour_space.c
@@ -28,6 +28,14 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+static inline int is_big_endian( )
+{
+       union { int i; char c[ 4 ]; } big_endian_test;
+       big_endian_test.i = 1;
+
+       return big_endian_test.c[ 0 ] != 1;
+}
+
 static inline int convert_mlt_to_av_cs( mlt_image_format format )
 {
        int value = 0;
@@ -87,12 +95,41 @@ static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *
                int size = avpicture_get_size( out_fmt, *width, *height );
                uint8_t *output = mlt_pool_alloc( size );
                convert_image( output, *image, out_fmt, in_fmt, *width, *height );
+
+               // Special case for alpha rgb input
+               if ( *format == mlt_image_rgb24a )
+               {
+                       register uint8_t *alpha = mlt_frame_get_alpha_mask( this );
+                       register int len = *width * *height;
+                       register uint8_t *bits = *image;
+                       register int n = ( len + 7 ) / 8;
+
+                       if( !is_big_endian( ) )
+                               bits += 3;
+
+                       // Extract alpha mask from the image using Duff's Device
+                       switch( len % 8 )
+                       {
+                               case 0: do { *alpha ++ = *bits; bits += 4;
+                               case 7:          *alpha ++ = *bits; bits += 4;
+                               case 6:          *alpha ++ = *bits; bits += 4;
+                               case 5:          *alpha ++ = *bits; bits += 4;
+                               case 4:          *alpha ++ = *bits; bits += 4;
+                               case 3:          *alpha ++ = *bits; bits += 4;
+                               case 2:          *alpha ++ = *bits; bits += 4;
+                               case 1:          *alpha ++ = *bits; bits += 4;
+                                               }
+                                               while( --n );
+                       }
+               }
+
+               // Update the output
                *image = output;
                *format = output_format;
                mlt_properties_set_data( properties, "image", output, size, mlt_pool_release, NULL );
                mlt_properties_set_int( properties, "format", output_format );
 
-               // Special case for alpha rgb - merge the alpha mask when it exists
+               // Special case for alpha rgb output
                if ( *format == mlt_image_rgb24a )
                {
                        // Fetch the alpha
@@ -103,11 +140,9 @@ static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *
                                register uint8_t *bits = *image;
                                register int len = *width * *height;
                                register int n = ( len + 7 ) / 8;
-
-                               // TODO: Proper check for big endian systems
-                               #ifndef __DARWIN__
-                               bits += 3;
-                               #endif
+                               
+                               if( !is_big_endian( ) )
+                                       bits += 3;
 
                                // Merge the alpha mask into the RGB image using Duff's Device
                                switch( len % 8 )