/* pngwtran.c - transforms the data in a row for PNG writers
*
- * Last changed in libpng 1.5.6 [November 3, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.0 [February 14, 2013]
+ * Copyright (c) 1998-2013 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*
* transformations is significant.
*/
void /* PRIVATE */
-png_do_write_transformations(png_structp png_ptr, png_row_infop row_info)
+png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info)
{
png_debug(1, "in png_do_write_transformations");
{
png_bytep bp = row;
png_size_t i;
- png_byte mask;
+ unsigned int mask;
png_size_t row_bytes = row_info->rowbytes;
if (bit_depth->gray == 1 && row_info->bit_depth == 2)
for (i = 0; i < row_bytes; i++, bp++)
{
- png_uint_16 v;
int j;
+ unsigned int v, out;
v = *bp;
- *bp = 0;
+ out = 0;
for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0])
{
if (j > 0)
- *bp |= (png_byte)((v << j) & 0xff);
+ out |= v << j;
else
- *bp |= (png_byte)((v >> (-j)) & mask);
+ out |= (v >> (-j)) & mask;
}
+
+ *bp = (png_byte)(out & 0xff);
}
}
for (i = 0; i < istop; i++, bp++)
{
- png_uint_16 v;
+ const unsigned int c = i%channels;
int j;
- int c = (int)(i%channels);
+ unsigned int v, out;
v = *bp;
- *bp = 0;
+ out = 0;
for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
{
if (j > 0)
- *bp |= (png_byte)((v << j) & 0xff);
+ out |= v << j;
else
- *bp |= (png_byte)((v >> (-j)) & 0xff);
+ out |= v >> (-j);
}
+
+ *bp = (png_byte)(out & 0xff);
}
}
for (bp = row, i = 0; i < istop; i++)
{
- int c = (int)(i%channels);
- png_uint_16 value, v;
+ const unsigned int c = i%channels;
int j;
+ unsigned int value, v;
- v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
+ v = png_get_uint_16(bp);
value = 0;
for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
{
if (j > 0)
- value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
+ value |= v << j;
else
- value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
+ value |= v >> (-j);
}
- *bp++ = (png_byte)(value >> 8);
+ *bp++ = (png_byte)((value >> 8) & 0xff);
*bp++ = (png_byte)(value & 0xff);
}
}