/* pngwrite.c - general routines to write a PNG file
*
- * Last changed in libpng 1.6.2 [April 25, 2013]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.9 [February 6, 2014]
+ * Copyright (c) 1998-2014 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.)
*
}
}
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+/* Performs intrapixel differencing */
+static void
+png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_write_intrapixel");
+
+ if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
+ {
+ int bytes_per_pixel;
+ png_uint_32 row_width = row_info->width;
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ bytes_per_pixel = 3;
+
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 4;
+
+ else
+ return;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ *(rp) = (png_byte)((*rp - *(rp + 1)) & 0xff);
+ *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff);
+ }
+ }
+
+#ifdef PNG_WRITE_16BIT_SUPPORTED
+ else if (row_info->bit_depth == 16)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ bytes_per_pixel = 6;
+
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 8;
+
+ else
+ return;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1);
+ png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3);
+ png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5);
+ png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL);
+ png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL);
+ *(rp ) = (png_byte)((red >> 8) & 0xff);
+ *(rp + 1) = (png_byte)(red & 0xff);
+ *(rp + 4) = (png_byte)((blue >> 8) & 0xff);
+ *(rp + 5) = (png_byte)(blue & 0xff);
+ }
+ }
+#endif /* PNG_WRITE_16BIT_SUPPORTED */
+ }
+}
+#endif /* PNG_MNG_FEATURES_SUPPORTED */
+
/* Called by user to write a row of image data */
void PNGAPI
png_write_row(png_structrp png_ptr, png_const_bytep row)
if (image->format & PNG_FORMAT_FLAG_ALPHA)
{
- if (image->format & PNG_FORMAT_FLAG_AFIRST)
- {
- aindex = -1;
- ++input_row; /* To point to the first component */
- ++output_row;
- }
+# ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
+ if (image->format & PNG_FORMAT_FLAG_AFIRST)
+ {
+ aindex = -1;
+ ++input_row; /* To point to the first component */
+ ++output_row;
+ }
- else
+ else
+# endif
aindex = channels;
}
png_bytep row_end;
int aindex;
- if (image->format & PNG_FORMAT_FLAG_AFIRST)
- {
- aindex = -1;
- ++input_row; /* To point to the first component */
- ++output_row;
- }
+# ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
+ if (image->format & PNG_FORMAT_FLAG_AFIRST)
+ {
+ aindex = -1;
+ ++input_row; /* To point to the first component */
+ ++output_row;
+ }
- else
+ else
+# endif
aindex = channels;
/* Use row_end in place of a loop counter: */
const png_uint_32 format = image->format;
const int channels = PNG_IMAGE_SAMPLE_CHANNELS(format);
-# ifdef PNG_FORMAT_BGR_SUPPORTED
+# if defined(PNG_FORMAT_BGR_SUPPORTED) &&\
+ defined(PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED)
const int afirst = (format & PNG_FORMAT_FLAG_AFIRST) != 0 &&
(format & PNG_FORMAT_FLAG_ALPHA) != 0;
# else