static int column_all_dark( hb_buffer_t* buf, int top, int bottom, int col )
{
int stride = buf->plane[0].stride;
int height = buf->plane[0].height - top - bottom;
uint8_t *luma = buf->plane[0].data + stride * top + col;
// compute the average value of the column
int i = height, avg = 0, row = 0;
for ( ; --i >= 0; row += stride )
{
avg += clampBlack( luma[row] );
}
avg /= height;
if ( avg >= DARK )
return 0;
// since we're trying to detect smooth borders, only take the column if
// all pixels are within +-16 of the average.
i = height, row = 0;
for ( ; --i >= 0; row += stride )
{
if ( absdiff( avg, clampBlack( luma[row] ) ) > 16 )
return 0;
}
return 1;
}
static int column_all_dark( hb_title_t *title, uint8_t* luma, int top, int bottom,
int col )
{
int stride = title->width;
int height = title->height - top - bottom;
luma += stride * top + col;
// compute the average value of the column
int i = height, avg = 0, row = 0;
for ( ; --i >= 0; row += stride )
{
avg += clampBlack( luma[row] );
}
avg /= height;
if ( avg >= DARK )
return 0;
// since we're trying to detect smooth borders, only take the column if
// all pixels are within +-16 of the average.
i = height, row = 0;
for ( ; --i >= 0; row += stride )
{
if ( absdiff( avg, clampBlack( luma[row] ) ) > 16 )
return 0;
}
return 1;
}
static int row_all_dark( hb_buffer_t* buf, int row )
{
int width = buf->plane[0].width;
int stride = buf->plane[0].stride;
uint8_t *luma = buf->plane[0].data + stride * row;
// compute the average luma value of the row
int i, avg = 0;
for ( i = 0; i < width; ++i )
{
avg += clampBlack( luma[i] );
}
avg /= width;
if ( avg >= DARK )
return 0;
// since we're trying to detect smooth borders, only take the row if
// all pixels are within +-16 of the average (this range is fairly coarse
// but there's a lot of quantization noise for luma values near black
// so anything less will fail to crop because of the noise).
for ( i = 0; i < width; ++i )
{
if ( absdiff( avg, clampBlack( luma[i] ) ) > 16 )
return 0;
}
return 1;
}
static int row_all_dark( hb_title_t *title, uint8_t* luma, int row )
{
luma += title->width * row;
// compute the average luma value of the row
int i, avg = 0;
for ( i = 0; i < title->width; ++i )
{
avg += clampBlack( luma[i] );
}
avg /= title->width;
if ( avg >= DARK )
return 0;
// since we're trying to detect smooth borders, only take the row if
// all pixels are within +-16 of the average (this range is fairly coarse
// but there's a lot of quantization noise for luma values near black
// so anything less will fail to crop because of the noise).
for ( i = 0; i < title->width; ++i )
{
if ( absdiff( avg, clampBlack( luma[i] ) ) > 16 )
return 0;
}
return 1;
}
