X-Git-Url: http://research.m1stereo.tv/gitweb?a=blobdiff_plain;f=src%2Fframework%2Fmlt_frame.c;h=e3e4f3f4ae25146ecc444aca1fca25884a3346a5;hb=519393231e6ab626f19bd01d4622d1c3759fcc93;hp=204eaae94a2ffd8c046d6763f6c2afaa953d20a7;hpb=13c13208272d0e14eadfc6d486e968de0a0d3e67;p=melted

diff --git a/src/framework/mlt_frame.c b/src/framework/mlt_frame.c
index 204eaae..e3e4f3f 100644
--- a/src/framework/mlt_frame.c
+++ b/src/framework/mlt_frame.c
@@ -200,6 +200,8 @@ int mlt_frame_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *for
 	mlt_properties properties = mlt_frame_properties( this );
 	mlt_get_image get_image = mlt_frame_pop_get_image( this );
 	mlt_producer producer = mlt_properties_get_data( properties, "test_card_producer", NULL );
+
+	*width = *width >> 1 << 1;
 	
 	if ( get_image != NULL )
 	{
@@ -226,6 +228,7 @@ int mlt_frame_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *for
 			mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
 			mlt_properties_set_int( properties, "width", *width );
 			mlt_properties_set_int( properties, "height", *height );
+			mlt_properties_set_double( properties, "aspect_ratio", mlt_frame_get_aspect_ratio( test_frame ) );
 			mlt_properties_set( properties, "rescale.interp", "none" );
 			mlt_properties_set( properties, "scale", "off" );
 		}
@@ -339,50 +342,57 @@ int mlt_frame_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *for
 	return 0;
 }
 
-unsigned char *mlt_frame_get_waveform( mlt_frame this, double fps, int w, int h )
+unsigned char *mlt_frame_get_waveform( mlt_frame this, int w, int h )
 {
-	/* Currently, w is not honored - the user must scale to desired height.
-	   Get the integer property waveform_width after calling to see the 
-	   produced width (currently equal to # samples). */
 	int16_t *pcm = NULL;
 	mlt_properties properties = mlt_frame_properties( this );
 	mlt_audio_format format = mlt_audio_pcm;
-	int frequency = 32000; /* lower frequency available? */
+	int frequency = 32000; // lower frequency available?
 	int channels = 2;
+	double fps = mlt_properties_get_double( properties, "fps" );
 	int samples = mlt_sample_calculator( fps, frequency, mlt_frame_get_position( this ) );
 	
-	/* get the pcm data */
+	// Get the pcm data
 	mlt_frame_get_audio( this, &pcm, &format, &frequency, &channels, &samples );
-	mlt_properties_set_int( properties, "waveform_width", samples );
 	
-	/* make an 8-bit buffer large enough to hold rendering */
-	int size = samples * h;
+	// Make an 8-bit buffer large enough to hold rendering
+	int size = w * h;
 	unsigned char *bitmap = ( unsigned char* )mlt_pool_alloc( size );
 	if ( bitmap != NULL )
 		memset( bitmap, 0, size );
 	mlt_properties_set_data( properties, "waveform", bitmap, size, ( mlt_destructor )mlt_pool_release, NULL );
 	
-	/* render - pcm data has channels interleaved */
-	int vertical_resolution = h / channels;
+	// Render vertical lines
+	int16_t *ubound = pcm + samples * channels;
+	int skip = samples / w - 1;
 	int i, j, k;
 	
-	for ( i = 0; i < samples; i++ )
+	// Iterate sample stream and along x coordinate
+	for ( i = 0; i < w && pcm < ubound; i++ )
 	{
+		// pcm data has channels interleaved
 		for ( j = 0; j < channels; j++ )
 		{
-			/* the height of a "bar" is the ratio of the sample multiplied by the vertical resolution */
-			int pcm_scaled = ( int )( ( double )( *pcm ) / 32767 * vertical_resolution );
-			int height = pcm_scaled < 0 ? -pcm_scaled : pcm_scaled;
-			int offset = j * samples * vertical_resolution;
-			int displacement = pcm_scaled < 0 ? ( vertical_resolution / 2 ) : ( vertical_resolution / 2 - pcm_scaled );
-			unsigned char *p = &bitmap[ offset + i + displacement * samples ];
+			// Determine sample's magnitude from 2s complement;
+			int pcm_magnitude = *pcm < 0 ? ~(*pcm) + 1 : *pcm;
+			// The height of a line is the ratio of the magnitude multiplied by 
+			// half the vertical resolution
+			int height = ( int )( ( double )( pcm_magnitude ) / 32768 * h / 2 );
+			// Determine the starting y coordinate - left channel above center,
+			// right channel below - currently assumes 2 channels
+			int displacement = ( h / 2 ) - ( 1 - j ) * height;
+			// Position buffer pointer using y coordinate, stride, and x coordinate
+			unsigned char *p = &bitmap[ i + displacement * w ];
 			
+			// Draw vertical line
 			for ( k = 0; k < height; k++ )
-				p[ samples * k ] = 0xFF;
+				p[ w * k ] = 0xFF;
 			
 			pcm++;
 		}
+		pcm += skip * channels;
 	}
+
 	return bitmap;
 }