+ /**
+ * Analyzes a frame to detect interlacing artifacts
+ * and returns true if interlacing (combing) is found.
+ *
+ * Code taken from Thomas Oestreich's 32detect filter
+ * in the Transcode project, with minor formatting changes.
+ *
+ * @param buf An hb_buffer structure holding valid frame data
+ * @param width The frame's width in pixels
+ * @param height The frame's height in pixels
+ * @param color_equal Sensitivity for detecting similar colors
+ * @param color_diff Sensitivity for detecting different colors
+ * @param threshold Sensitivity for flagging planes as combed
+ * @param prog_equal Sensitivity for detecting similar colors on progressive frames
+ * @param prog_diff Sensitivity for detecting different colors on progressive frames
+ * @param prog_threshold Sensitivity for flagging progressive frames as combed
+ */
+int hb_detect_comb( hb_buffer_t * buf, int width, int height, int color_equal, int color_diff, int threshold, int prog_equal, int prog_diff, int prog_threshold )
+{
+ int j, k, n, off, cc_1, cc_2, cc[3];
+ // int flag[3] ; // debugging flag
+ uint16_t s1, s2, s3, s4;
+ cc_1 = 0; cc_2 = 0;
+
+ int offset = 0;
+
+ if ( buf->flags & 16 )
+ {
+ /* Frame is progressive, be more discerning. */
+ color_diff = prog_diff;
+ color_equal = prog_equal;
+ threshold = prog_threshold;
+ }
+
+ /* One pas for Y, one pass for Cb, one pass for Cr */
+ for( k = 0; k < 3; k++ )
+ {
+ if( k == 1 )
+ {
+ /* Y has already been checked, now offset by Y's dimensions
+ and divide all the other values by 2, since Cr and Cb
+ are half-size compared to Y. */
+ offset = width * height;
+ width >>= 1;
+ height >>= 1;
+ }
+ else if ( k == 2 )
+ {
+ /* Y and Cb are done, so the offset needs to be bumped
+ so it's width*height + (width / 2) * (height / 2) */
+ offset *= 5/4;
+ }
+
+ for( j = 0; j < width; ++j )
+ {
+ off = 0;
+
+ for( n = 0; n < ( height - 4 ); n = n + 2 )
+ {
+ /* Look at groups of 4 sequential horizontal lines */
+ s1 = ( ( buf->data + offset )[ off + j ] & 0xff );
+ s2 = ( ( buf->data + offset )[ off + j + width ] & 0xff );
+ s3 = ( ( buf->data + offset )[ off + j + 2 * width ] & 0xff );
+ s4 = ( ( buf->data + offset )[ off + j + 3 * width ] & 0xff );
+
+ /* Note if the 1st and 2nd lines are more different in
+ color than the 1st and 3rd lines are similar in color.*/
+ if ( ( abs( s1 - s3 ) < color_equal ) &&
+ ( abs( s1 - s2 ) > color_diff ) )
+ ++cc_1;
+
+ /* Note if the 2nd and 3rd lines are more different in
+ color than the 2nd and 4th lines are similar in color.*/
+ if ( ( abs( s2 - s4 ) < color_equal ) &&
+ ( abs( s2 - s3 ) > color_diff) )
+ ++cc_2;
+
+ /* Now move down 2 horizontal lines before starting over.*/
+ off += 2 * width;
+ }
+ }
+
+ // compare results
+ /* The final cc score for a plane is the percentage of combed pixels it contains.
+ Because sensitivity goes down to hundreths of a percent, multiply by 1000
+ so it will be easy to compare against the threhold value which is an integer. */
+ cc[k] = (int)( ( cc_1 + cc_2 ) * 1000.0 / ( width * height ) );
+ }
+
+
+ /* HandBrake is all yuv420, so weight the average percentage of all 3 planes accordingly.*/
+ int average_cc = ( 2 * cc[0] + ( cc[1] / 2 ) + ( cc[2] / 2 ) ) / 3;
+
+ /* Now see if that average percentage of combed pixels surpasses the threshold percentage given by the user.*/
+ if( average_cc > threshold )
+ {
+#if 0
+ hb_log("Average %i combed (Threshold %i) %i/%i/%i | PTS: %lld (%fs) %s", average_cc, threshold, cc[0], cc[1], cc[2], buf->start, (float)buf->start / 90000, (buf->flags & 16) ? "Film" : "Video" );
+#endif
+ return 1;
+ }
+
+#if 0
+ hb_log("SKIPPED Average %i combed (Threshold %i) %i/%i/%i | PTS: %lld (%fs) %s", average_cc, threshold, cc[0], cc[1], cc[2], buf->start, (float)buf->start / 90000, (buf->flags & 16) ? "Film" : "Video" );
+#endif
+
+ /* Reaching this point means no combing detected. */
+ return 0;
+
+}
+
+/**
+ * Calculates job width and height for anamorphic content,
+ *
+ * @param job Handle to hb_job_t
+ * @param output_width Pointer to returned storage width
+ * @param output_height Pointer to returned storage height
+ * @param output_par_width Pointer to returned pixel width
+ @ param output_par_height Pointer to returned pixel height
+ */
+void hb_set_anamorphic_size( hb_job_t * job,
+ int *output_width, int *output_height,
+ int *output_par_width, int *output_par_height )
+{
+ /* Set up some variables to make the math easier to follow. */
+ hb_title_t * title = job->title;
+ int cropped_width = title->width - job->crop[2] - job->crop[3] ;
+ int cropped_height = title->height - job->crop[0] - job->crop[1] ;
+ double storage_aspect = (double)cropped_width / (double)cropped_height;
+ int mod = job->anamorphic.modulus ? job->anamorphic.modulus : 16;
+ double aspect = title->aspect;
+
+ int pixel_aspect_width = job->anamorphic.par_width;
+ int pixel_aspect_height = job->anamorphic.par_height;
+
+ /* If a source was really NTSC or PAL and the user specified ITU PAR
+ values, replace the standard PAR values with the ITU broadcast ones. */
+ if( title->width == 720 && job->anamorphic.itu_par )
+ {
+ // convert aspect to a scaled integer so we can test for 16:9 & 4:3
+ // aspect ratios ignoring insignificant differences in the LSBs of
+ // the floating point representation.
+ int iaspect = aspect * 9.;
+
+ /* Handle ITU PARs */
+ if (title->height == 480)
+ {
+ /* It's NTSC */
+ if (iaspect == 16)
+ {
+ /* It's widescreen */
+ pixel_aspect_width = 40;
+ pixel_aspect_height = 33;
+ }
+ else if (iaspect == 12)
+ {
+ /* It's 4:3 */
+ pixel_aspect_width = 10;
+ pixel_aspect_height = 11;
+ }
+ }
+ else if (title->height == 576)
+ {
+ /* It's PAL */
+ if(iaspect == 16)
+ {
+ /* It's widescreen */
+ pixel_aspect_width = 16;
+ pixel_aspect_height = 11;
+ }
+ else if (iaspect == 12)
+ {
+ /* It's 4:3 */
+ pixel_aspect_width = 12;
+ pixel_aspect_height = 11;
+ }
+ }
+ }
+
+ /* Figure out what width the source would display at. */
+ int source_display_width = cropped_width * (double)pixel_aspect_width /
+ (double)pixel_aspect_height ;
+
+ /*
+ 3 different ways of deciding output dimensions:
+ - 1: Strict anamorphic, preserve source dimensions
+ - 2: Loose anamorphic, round to mod16 and preserve storage aspect ratio
+ - 3: Power user anamorphic, specify everything
+ */
+ int width, height;
+ switch( job->anamorphic.mode )
+ {
+ case 1:
+ /* Strict anamorphic */
+ *output_width = cropped_width;
+ *output_height = cropped_height;
+ *output_par_width = title->pixel_aspect_width;
+ *output_par_height = title->pixel_aspect_height;
+ break;
+
+ case 2:
+ /* "Loose" anamorphic.
+ - Uses mod16-compliant dimensions,
+ - Allows users to set the width
+ */
+ width = job->width;
+ // height: Gets set later, ignore user job->height value
+
+ /* Gotta handle bounding dimensions.
+ If the width is too big, just reset it with no rescaling.
+ Instead of using the aspect-scaled job height,
+ we need to see if the job width divided by the storage aspect
+ is bigger than the max. If so, set it to the max (this is sloppy).
+ If not, set job height to job width divided by storage aspect.
+ */
+
+ if ( job->maxWidth && (job->maxWidth < job->width) )
+ width = job->maxWidth;
+
+ /* Time to get picture width that divide cleanly.*/
+ width = MULTIPLE_MOD( width, mod);
+
+ /* Verify these new dimensions don't violate max height and width settings */
+ if ( job->maxWidth && (job->maxWidth < job->width) )
+ width = job->maxWidth;
+
+ height = ((double)width / storage_aspect) + 0.5;
+
+ if ( job->maxHeight && (job->maxHeight < height) )
+ height = job->maxHeight;
+
+ /* Time to get picture height that divide cleanly.*/
+ height = MULTIPLE_MOD( height, mod);
+
+ /* Verify these new dimensions don't violate max height and width settings */
+ if ( job->maxHeight && (job->maxHeight < height) )
+ height = job->maxHeight;
+
+ /* The film AR is the source's display width / cropped source height.
+ The output display width is the output height * film AR.
+ The output PAR is the output display width / output storage width. */
+ pixel_aspect_width = height * source_display_width / cropped_height;
+ pixel_aspect_height = width;
+
+ /* Pass the results back to the caller */
+ *output_width = width;
+ *output_height = height;
+ break;
+
+ case 3:
+ /* Anamorphic 3: Power User Jamboree
+ - Set everything based on specified values */
+
+ /* Use specified storage dimensions */
+ width = job->width;
+ height = job->height;
+
+ /* Bind to max dimensions */
+ if( job->maxWidth && width > job->maxWidth )
+ width = job->maxWidth;
+ if( job->maxHeight && height > job->maxHeight )
+ height = job->maxHeight;
+
+ /* Time to get picture dimensions that divide cleanly.*/
+ width = MULTIPLE_MOD( width, mod);
+ height = MULTIPLE_MOD( height, mod);
+
+ /* Verify we're still within max dimensions */
+ if( job->maxWidth && width > job->maxWidth )
+ width = job->maxWidth - (mod/2);
+ if( job->maxHeight && height > job->maxHeight )
+ height = job->maxHeight - (mod/2);
+
+ /* Re-ensure we have picture dimensions that divide cleanly. */
+ width = MULTIPLE_MOD( width, mod );
+ height = MULTIPLE_MOD( height, mod );
+
+ /* That finishes the storage dimensions. On to display. */
+ if( job->anamorphic.dar_width && job->anamorphic.dar_height )
+ {
+ /* We need to adjust the PAR to produce this aspect. */
+ pixel_aspect_width = height * job->anamorphic.dar_width / job->anamorphic.dar_height;
+ pixel_aspect_height = width;
+ }
+ else
+ {
+ /* If we're doing ana 3 and not specifying a DAR, care needs to be taken.
+ This indicates a PAR is potentially being set by the interface. But
+ this is an output PAR, to correct a source, and it should not be assumed
+ that it properly creates a display aspect ratio when applied to the source,
+ which could easily be stored in a different resolution. */
+ if( job->anamorphic.keep_display_aspect )
+ {
+ /* We can ignore the possibility of a PAR change */
+ pixel_aspect_width = height * ( (double)source_display_width / (double)cropped_height );
+ pixel_aspect_height = width;
+ }
+ else
+ {
+ int output_display_width = width * (double)pixel_aspect_width /
+ (double)pixel_aspect_height;
+ pixel_aspect_width = output_display_width;
+ pixel_aspect_height = width;
+ }
+ }
+
+ /* Back to caller */
+ *output_width = width;
+ *output_height = height;
+ break;
+ }
+
+ /* While x264 is smart enough to reduce fractions on its own, libavcodec
+ needs some help with the math, so lose superfluous factors. */
+ hb_reduce( output_par_width, output_par_height,
+ pixel_aspect_width, pixel_aspect_height );
+}
+