sergiotarxz/libvips
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

stop strip tiff read using tiny tiles

Browse Source 
Strip TIFFs with rowperstrip of 1 used to use 1-pixel high cache tiles.
This could slow reading. This patch sets a minimum tile height near 16
but a multiple of the strip size.
This commit is contained in:
John Cupitt 2022-04-09 16:38:47 +01:00
parent 6c03343581
commit 6eae6fcf4b
1 changed files with 12 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
libvips/foreign/tiff2vips.c
View File

@ -2203,16 +2203,10 @@ rtiff_stripwise_generate( VipsRegion *or,
g_assert( VIPS_RECT_BOTTOM( r ) <= or->im->Ysize );
/* If we're reading more than one page, tiles won't fall on strip
* boundaries.
* boundaries. Tiles may be contain several strips.
*/
/* Tiles should always be a strip in height, unless it's the final
* strip in the image.
*/
g_assert( r->height ==
VIPS_MIN( read_height, or->im->Ysize - r->top ) );
/* And check that y_pos is correct. It should be, since we are inside
/* Check that y_pos is correct. It should be, since we are inside
* a vips_sequential().
*/
if( r->top != rtiff->y_pos ) {
@ -2340,6 +2334,7 @@ rtiff_read_stripwise( Rtiff *rtiff, VipsImage *out )
vips_object_local_array( VIPS_OBJECT( out ), 4 );
VipsImage *in;
int tile_height;
#ifdef DEBUG
printf( "tiff2vips: rtiff_read_stripwise\n" );
@ -2408,13 +2403,21 @@ rtiff_read_stripwise( Rtiff *rtiff, VipsImage *out )
/* rows_per_strip can be very large if this is a separate plane image,
* beware.
*
* Some images have very small rowsperstrip which will cause a lot of
* work for the tilecache -- set a min size for tiles which is a
* multiple of rowsperstrip.
*/
tile_height = VIPS_MAX(
VIPS_ROUND_DOWN( 16, rtiff->header.read_height ),
rtiff->header.read_height );
if(
vips_image_generate( t[0],
NULL, rtiff_stripwise_generate, NULL,
rtiff, NULL ) ||
vips_sequential( t[0], &t[1],
"tile_height", rtiff->header.read_height,
"tile_height", tile_height,
NULL ) ||
rtiff_unpremultiply( rtiff, t[1], &t[2] ) )
return( -1 );