[devel] Fix png_get_current_row_number in the interlaced case.

This commit is contained in:
John Bowler 2011-02-12 08:59:17 -06:00 committed by Glenn Randers-Pehrson
parent 9c69360e97
commit 5432c01ffd
4 changed files with 23 additions and 2 deletions

4
png.h
View File

@ -1477,6 +1477,10 @@ PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
* row number is still the row in the final, de-interlaced, image but the row
* only contains the data of the current pass - consult png_row_info for the
* actual width of the row!
*
* In contrast the row numbers passed to the progressive reader and sequential
* reader callbacks are actually the rows in the input data - so the row in the
* interlaced pass for an interlaced image.
*/
PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp));
PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp));

View File

@ -703,11 +703,21 @@ png_get_user_transform_ptr(png_const_structp png_ptr)
}
#endif
#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
png_uint_32 PNGAPI
png_get_current_row_number(png_const_structp png_ptr)
{
/* This API returns the row in output, not the input row: */
if (png_ptr != NULL)
{
if (png_ptr->interlaced == PNG_INTERLACE_NONE)
return png_ptr->row_number;
else if (png_ptr->interlaced == PNG_INTERLACE_ADAM7)
return PNG_ROW_FROM_PASS_ROW(png_ptr->row_number, png_ptr->pass);
/* Else something bad is happening: */
}
return PNG_UINT_32_MAX; /* help the app not to fail silently */
}
@ -718,6 +728,7 @@ png_get_current_pass_number(png_const_structp png_ptr)
return png_ptr->pass;
return 8; /* invalid */
}
#endif /* PNG_USER_TRANSFORM_INFO_SUPPORTED */
#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
PNG_WRITE_USER_TRANSFORM_SUPPORTED */
#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */

View File

@ -3072,7 +3072,13 @@ progressive_row(png_structp pp, png_bytep new_row, png_uint_32 y, int pass)
* us the y in the sub-image:
*/
if (dp->do_interlace && dp->interlace_type == PNG_INTERLACE_ADAM7)
{
if (pass != png_get_current_pass_number(pp))
png_error(pp, "png_get_current_pass_number is broken");
y = PNG_ROW_FROM_PASS_ROW(y, pass);
if (y != png_get_current_row_number(pp))
png_error(pp, "png_get_current_row_number is broken");
}
/* Validate this just in case. */
if (y >= dp->h)

View File

@ -148,6 +148,7 @@
#define PNG_WRITE_INVERT_ALPHA_SUPPORTED
#define PNG_sCAL_SUPPORTED
#define PNG_WRITE_zTXt_SUPPORTED
#define PNG_USER_TRANSFORM_INFO_SUPPORTED
#define PNG_sBIT_SUPPORTED
#define PNG_cHRM_SUPPORTED
#define PNG_bKGD_SUPPORTED
@ -155,7 +156,6 @@
#define PNG_WRITE_iTXt_SUPPORTED
#define PNG_oFFs_SUPPORTED
#define PNG_USER_TRANSFORM_PTR_SUPPORTED
#define PNG_USER_TRANSFORM_INFO_SUPPORTED
#define PNG_hIST_SUPPORTED
#define PNG_iCCP_SUPPORTED
#define PNG_sRGB_SUPPORTED