/* pngwutil.c - utilities to write a PNG file
*
- * Last changed in libpng 1.6.21 [January 15, 2016]
- * Copyright (c) 1998-2002,2004,2006-2015 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.)
+ * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
+ * Copyright (c) 1996-1997 Andreas Dilger
+ * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
void PNGAPI
png_save_uint_32(png_bytep buf, png_uint_32 i)
{
- buf[0] = (png_byte)(i >> 24);
- buf[1] = (png_byte)(i >> 16);
- buf[2] = (png_byte)(i >> 8);
- buf[3] = (png_byte)(i );
+ buf[0] = (png_byte)((i >> 24) & 0xffU);
+ buf[1] = (png_byte)((i >> 16) & 0xffU);
+ buf[2] = (png_byte)((i >> 8) & 0xffU);
+ buf[3] = (png_byte)( i & 0xffU);
}
/* Place a 16-bit number into a buffer in PNG byte order.
void PNGAPI
png_save_uint_16(png_bytep buf, unsigned int i)
{
- buf[0] = (png_byte)(i >> 8);
- buf[1] = (png_byte)(i );
+ buf[0] = (png_byte)((i >> 8) & 0xffU);
+ buf[1] = (png_byte)( i & 0xffU);
}
#endif
/* Write the rest of the 8 byte signature */
png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
- (png_size_t)(8 - png_ptr->sig_bytes));
+ (size_t)(8 - png_ptr->sig_bytes));
if (png_ptr->sig_bytes < 3)
png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
* given to png_write_chunk_header().
*/
void PNGAPI
-png_write_chunk_data(png_structrp png_ptr, png_const_bytep data,
- png_size_t length)
+png_write_chunk_data(png_structrp png_ptr, png_const_bytep data, size_t length)
{
/* Write the data, and run the CRC over it */
if (png_ptr == NULL)
/* Write the crc in a single operation */
png_save_uint_32(buf, png_ptr->crc);
- png_write_data(png_ptr, buf, (png_size_t)4);
+ png_write_data(png_ptr, buf, 4);
}
/* Write a PNG chunk all at once. The type is an array of ASCII characters
*/
static void
png_write_complete_chunk(png_structrp png_ptr, png_uint_32 chunk_name,
- png_const_bytep data, png_size_t length)
+ png_const_bytep data, size_t length)
{
if (png_ptr == NULL)
return;
/* This is the API that calls the internal function above. */
void PNGAPI
png_write_chunk(png_structrp png_ptr, png_const_bytep chunk_string,
- png_const_bytep data, png_size_t length)
+ png_const_bytep data, size_t length)
{
png_write_complete_chunk(png_ptr, PNG_CHUNK_FROM_STRING(chunk_string), data,
- length);
+ length);
}
/* This is used below to find the size of an image to pass to png_deflate_claim,
/* Initialize the compressor for the appropriate type of compression. */
static int
png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
- png_alloc_size_t data_size)
+ png_alloc_size_t data_size)
{
if (png_ptr->zowner != 0)
{
png_ptr->zstream.avail_out = 0;
/* Now initialize if required, setting the new parameters, otherwise just
- * to a simple reset to the previous parameters.
+ * do a simple reset to the previous parameters.
*/
if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
ret = deflateReset(&png_ptr->zstream);
else
{
ret = deflateInit2(&png_ptr->zstream, level, method, windowBits,
- memLevel, strategy);
+ memLevel, strategy);
if (ret == Z_OK)
png_ptr->flags |= PNG_FLAG_ZSTREAM_INITIALIZED;
static void
png_text_compress_init(compression_state *comp, png_const_bytep input,
- png_alloc_size_t input_len)
+ png_alloc_size_t input_len)
{
comp->input = input;
comp->input_len = input_len;
/* Compress the data in the compression state input */
static int
png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
- compression_state *comp, png_uint_32 prefix_len)
+ compression_state *comp, png_uint_32 prefix_len)
{
int ret;
/* Compress the data */
ret = deflate(&png_ptr->zstream,
- input_len > 0 ? Z_NO_FLUSH : Z_FINISH);
+ input_len > 0 ? Z_NO_FLUSH : Z_FINISH);
/* Claw back input data that was not consumed (because avail_in is
* reset above every time round the loop).
int interlace_type)
{
png_byte buf[13]; /* Buffer to store the IHDR info */
+ int is_invalid_depth;
png_debug(1, "in png_write_IHDR");
break;
case PNG_COLOR_TYPE_RGB:
+ is_invalid_depth = (bit_depth != 8);
#ifdef PNG_WRITE_16BIT_SUPPORTED
- if (bit_depth != 8 && bit_depth != 16)
-#else
- if (bit_depth != 8)
+ is_invalid_depth = (is_invalid_depth && bit_depth != 16);
#endif
+ if (is_invalid_depth)
png_error(png_ptr, "Invalid bit depth for RGB image");
png_ptr->channels = 3;
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
- if (bit_depth != 8 && bit_depth != 16)
+ is_invalid_depth = (bit_depth != 8);
+#ifdef PNG_WRITE_16BIT_SUPPORTED
+ is_invalid_depth = (is_invalid_depth && bit_depth != 16);
+#endif
+ if (is_invalid_depth)
png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
png_ptr->channels = 2;
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
+ is_invalid_depth = (bit_depth != 8);
#ifdef PNG_WRITE_16BIT_SUPPORTED
- if (bit_depth != 8 && bit_depth != 16)
-#else
- if (bit_depth != 8)
+ is_invalid_depth = (is_invalid_depth && bit_depth != 16);
#endif
+ if (is_invalid_depth)
png_error(png_ptr, "Invalid bit depth for RGBA image");
png_ptr->channels = 4;
buf[12] = (png_byte)interlace_type;
/* Write the chunk */
- png_write_complete_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
+ png_write_complete_chunk(png_ptr, png_IHDR, buf, 13);
if ((png_ptr->do_filter) == PNG_NO_FILTERS)
{
buf[0] = pal_ptr->red;
buf[1] = pal_ptr->green;
buf[2] = pal_ptr->blue;
- png_write_chunk_data(png_ptr, buf, (png_size_t)3);
+ png_write_chunk_data(png_ptr, buf, 3);
}
#else
buf[0] = pal_ptr[i].red;
buf[1] = pal_ptr[i].green;
buf[2] = pal_ptr[i].blue;
- png_write_chunk_data(png_ptr, buf, (png_size_t)3);
+ png_write_chunk_data(png_ptr, buf, 3);
}
#endif
*/
void /* PRIVATE */
png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
- png_alloc_size_t input_len, int flush)
+ png_alloc_size_t input_len, int flush)
{
if (png_ptr->zowner != png_IDAT)
{
if (png_ptr->zbuffer_list == NULL)
{
png_ptr->zbuffer_list = png_voidcast(png_compression_bufferp,
- png_malloc(png_ptr, PNG_COMPRESSION_BUFFER_SIZE(png_ptr)));
+ png_malloc(png_ptr, PNG_COMPRESSION_BUFFER_SIZE(png_ptr)));
png_ptr->zbuffer_list->next = NULL;
}
optimize_cmf(data, png_image_size(png_ptr));
#endif
- png_write_complete_chunk(png_ptr, png_IDAT, data, size);
+ if (size > 0)
+ png_write_complete_chunk(png_ptr, png_IDAT, data, size);
png_ptr->mode |= PNG_HAVE_IDAT;
png_ptr->zstream.next_out = data;
optimize_cmf(data, png_image_size(png_ptr));
#endif
- png_write_complete_chunk(png_ptr, png_IDAT, data, size);
+ if (size > 0)
+ png_write_complete_chunk(png_ptr, png_IDAT, data, size);
png_ptr->zstream.avail_out = 0;
png_ptr->zstream.next_out = NULL;
png_ptr->mode |= PNG_HAVE_IDAT | PNG_AFTER_IDAT;
{
png_debug(1, "in png_write_IEND");
- png_write_complete_chunk(png_ptr, png_IEND, NULL, (png_size_t)0);
+ png_write_complete_chunk(png_ptr, png_IEND, NULL, 0);
png_ptr->mode |= PNG_HAVE_IEND;
}
/* file_gamma is saved in 1/100,000ths */
png_save_uint_32(buf, (png_uint_32)file_gamma);
- png_write_complete_chunk(png_ptr, png_gAMA, buf, (png_size_t)4);
+ png_write_complete_chunk(png_ptr, png_gAMA, buf, 4);
}
#endif
"Invalid sRGB rendering intent specified");
buf[0]=(png_byte)srgb_intent;
- png_write_complete_chunk(png_ptr, png_sRGB, buf, (png_size_t)1);
+ png_write_complete_chunk(png_ptr, png_sRGB, buf, 1);
}
#endif
png_uint_32 name_len;
png_byte new_name[80];
png_byte entrybuf[10];
- png_size_t entry_size = (spalette->depth == 8 ? 6 : 10);
- png_size_t palette_size = entry_size * spalette->nentries;
+ size_t entry_size = (spalette->depth == 8 ? 6 : 10);
+ size_t palette_size = entry_size * (size_t)spalette->nentries;
png_sPLT_entryp ep;
#ifndef PNG_POINTER_INDEXING_SUPPORTED
int i;
png_write_chunk_header(png_ptr, png_sPLT,
(png_uint_32)(name_len + 2 + palette_size));
- png_write_chunk_data(png_ptr, (png_bytep)new_name,
- (png_size_t)(name_len + 1));
+ png_write_chunk_data(png_ptr, (png_bytep)new_name, (size_t)(name_len + 1));
- png_write_chunk_data(png_ptr, &spalette->depth, (png_size_t)1);
+ png_write_chunk_data(png_ptr, &spalette->depth, 1);
/* Loop through each palette entry, writing appropriately */
#ifdef PNG_POINTER_INDEXING_SUPPORTED
png_write_sBIT(png_structrp png_ptr, png_const_color_8p sbit, int color_type)
{
png_byte buf[4];
- png_size_t size;
+ size_t size;
png_debug(1, "in png_write_sBIT");
/* Write the chunk out as it is */
png_write_complete_chunk(png_ptr, png_tRNS, trans_alpha,
- (png_size_t)num_trans);
+ (size_t)num_trans);
}
else if (color_type == PNG_COLOR_TYPE_GRAY)
}
png_save_uint_16(buf, tran->gray);
- png_write_complete_chunk(png_ptr, png_tRNS, buf, (png_size_t)2);
+ png_write_complete_chunk(png_ptr, png_tRNS, buf, 2);
}
else if (color_type == PNG_COLOR_TYPE_RGB)
#endif
{
png_app_warning(png_ptr,
- "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
+ "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
return;
}
- png_write_complete_chunk(png_ptr, png_tRNS, buf, (png_size_t)6);
+ png_write_complete_chunk(png_ptr, png_tRNS, buf, 6);
}
else
}
buf[0] = back->index;
- png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
+ png_write_complete_chunk(png_ptr, png_bKGD, buf, 1);
}
else if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
#endif
{
png_warning(png_ptr,
- "Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8");
+ "Ignoring attempt to write 16-bit bKGD chunk "
+ "when bit_depth is 8");
return;
}
- png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)6);
+ png_write_complete_chunk(png_ptr, png_bKGD, buf, 6);
}
else
}
png_save_uint_16(buf, back->gray);
- png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)2);
+ png_write_complete_chunk(png_ptr, png_bKGD, buf, 2);
+ }
+}
+#endif
+
+#ifdef PNG_WRITE_eXIf_SUPPORTED
+/* Write the Exif data */
+void /* PRIVATE */
+png_write_eXIf(png_structrp png_ptr, png_bytep exif, int num_exif)
+{
+ int i;
+ png_byte buf[1];
+
+ png_debug(1, "in png_write_eXIf");
+
+ png_write_chunk_header(png_ptr, png_eXIf, (png_uint_32)(num_exif));
+
+ for (i = 0; i < num_exif; i++)
+ {
+ buf[0] = exif[i];
+ png_write_chunk_data(png_ptr, buf, 1);
}
+
+ png_write_chunk_end(png_ptr);
}
#endif
for (i = 0; i < num_hist; i++)
{
png_save_uint_16(buf, hist[i]);
- png_write_chunk_data(png_ptr, buf, (png_size_t)2);
+ png_write_chunk_data(png_ptr, buf, 2);
}
png_write_chunk_end(png_ptr);
/* Write a tEXt chunk */
void /* PRIVATE */
png_write_tEXt(png_structrp png_ptr, png_const_charp key, png_const_charp text,
- png_size_t text_len)
+ size_t text_len)
{
png_uint_32 key_len;
png_byte new_key[80];
/* Compute the compressed data; do it now for the length */
png_text_compress_init(&comp, (png_const_bytep)text,
- text == NULL ? 0 : strlen(text));
+ text == NULL ? 0 : strlen(text));
if (png_text_compress(png_ptr, png_zTXt, &comp, key_len) != Z_OK)
png_error(png_ptr, png_ptr->zstream.msg);
png_const_charp lang, png_const_charp lang_key, png_const_charp text)
{
png_uint_32 key_len, prefix_len;
- png_size_t lang_len, lang_key_len;
+ size_t lang_len, lang_key_len;
png_byte new_key[82];
compression_state comp;
png_save_int_32(buf + 4, y_offset);
buf[8] = (png_byte)unit_type;
- png_write_complete_chunk(png_ptr, png_oFFs, buf, (png_size_t)9);
+ png_write_complete_chunk(png_ptr, png_oFFs, buf, 9);
}
#endif
#ifdef PNG_WRITE_pCAL_SUPPORTED
png_charpp params)
{
png_uint_32 purpose_len;
- png_size_t units_len, total_len;
+ size_t units_len, total_len;
png_size_tp params_len;
png_byte buf[10];
png_byte new_purpose[80];
total_len = purpose_len + units_len + 10;
params_len = (png_size_tp)png_malloc(png_ptr,
- (png_alloc_size_t)(nparams * (sizeof (png_size_t))));
+ (png_alloc_size_t)((png_alloc_size_t)nparams * (sizeof (size_t))));
/* Find the length of each parameter, making sure we don't count the
* null terminator for the last parameter.
png_save_int_32(buf + 4, X1);
buf[8] = (png_byte)type;
buf[9] = (png_byte)nparams;
- png_write_chunk_data(png_ptr, buf, (png_size_t)10);
- png_write_chunk_data(png_ptr, (png_const_bytep)units, (png_size_t)units_len);
+ png_write_chunk_data(png_ptr, buf, 10);
+ png_write_chunk_data(png_ptr, (png_const_bytep)units, (size_t)units_len);
for (i = 0; i < nparams; i++)
{
png_const_charp height)
{
png_byte buf[64];
- png_size_t wlen, hlen, total_len;
+ size_t wlen, hlen, total_len;
png_debug(1, "in png_write_sCAL_s");
png_save_uint_32(buf + 4, y_pixels_per_unit);
buf[8] = (png_byte)unit_type;
- png_write_complete_chunk(png_ptr, png_pHYs, buf, (png_size_t)9);
+ png_write_complete_chunk(png_ptr, png_pHYs, buf, 9);
}
#endif
buf[5] = mod_time->minute;
buf[6] = mod_time->second;
- png_write_complete_chunk(png_ptr, png_tIME, buf, (png_size_t)7);
+ png_write_complete_chunk(png_ptr, png_tIME, buf, 7);
}
#endif
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
/* Start of interlace block */
- static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+ static const png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
/* Offset to next interlace block */
- static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+ static const png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
/* Start of interlace block in the y direction */
- static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+ static const png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
/* Offset to next interlace block in the y direction */
- static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+ static const png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
#endif
png_alloc_size_t buf_size;
*/
if ((filters & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) != 0)
png_ptr->prev_row = png_voidcast(png_bytep,
- png_calloc(png_ptr, buf_size));
+ png_calloc(png_ptr, buf_size));
#endif /* WRITE_FILTER */
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
/* Start of interlace block */
- static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+ static const png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
/* Offset to next interlace block */
- static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+ static const png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
/* Start of interlace block in the y direction */
- static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+ static const png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
/* Offset to next interlace block in the y direction */
- static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+ static const png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
#endif
png_debug(1, "in png_write_finish_row");
{
if (png_ptr->prev_row != NULL)
memset(png_ptr->prev_row, 0,
- (png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels*
- png_ptr->usr_bit_depth, png_ptr->width)) + 1);
+ PNG_ROWBYTES(png_ptr->usr_channels *
+ png_ptr->usr_bit_depth, png_ptr->width) + 1);
return;
}
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
/* Start of interlace block */
- static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+ static const png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
/* Offset to next interlace block */
- static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+ static const png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
png_debug(1, "in png_do_write_interlace");
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
- sp = row + (png_size_t)(i >> 3);
+ sp = row + (size_t)(i >> 3);
value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01;
d |= (value << shift);
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
- sp = row + (png_size_t)(i >> 2);
+ sp = row + (size_t)(i >> 2);
value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03;
d |= (value << shift);
for (i = png_pass_start[pass]; i < row_width;
i += png_pass_inc[pass])
{
- sp = row + (png_size_t)(i >> 1);
+ sp = row + (size_t)(i >> 1);
value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f;
d |= (value << shift);
png_bytep dp;
png_uint_32 i;
png_uint_32 row_width = row_info->width;
- png_size_t pixel_bytes;
+ size_t pixel_bytes;
/* Start at the beginning */
dp = row;
i += png_pass_inc[pass])
{
/* Find out where the original pixel is */
- sp = row + (png_size_t)i * pixel_bytes;
+ sp = row + (size_t)i * pixel_bytes;
/* Move the pixel */
if (dp != sp)
*/
static void /* PRIVATE */
png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
- png_size_t row_bytes);
+ size_t row_bytes);
#ifdef PNG_WRITE_FILTER_SUPPORTED
-static png_size_t /* PRIVATE */
-png_setup_sub_row(png_structrp png_ptr, const png_uint_32 bpp,
- const png_size_t row_bytes, const png_size_t lmins)
+static size_t /* PRIVATE */
+png_setup_sub_row(png_structrp png_ptr, png_uint_32 bpp,
+ size_t row_bytes, size_t lmins)
{
png_bytep rp, dp, lp;
- png_size_t i;
- png_size_t sum = 0;
- int v;
+ size_t i;
+ size_t sum = 0;
+ unsigned int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_SUB;
i++, rp++, dp++)
{
v = *dp = *rp;
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
}
for (lp = png_ptr->row_buf + 1; i < row_bytes;
i++, rp++, lp++, dp++)
{
v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
if (sum > lmins) /* We are already worse, don't continue. */
break;
return (sum);
}
-static png_size_t /* PRIVATE */
-png_setup_up_row(png_structrp png_ptr, const png_size_t row_bytes,
- const png_size_t lmins)
+static void /* PRIVATE */
+png_setup_sub_row_only(png_structrp png_ptr, png_uint_32 bpp,
+ size_t row_bytes)
+{
+ png_bytep rp, dp, lp;
+ size_t i;
+
+ png_ptr->try_row[0] = PNG_FILTER_VALUE_SUB;
+
+ for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1; i < bpp;
+ i++, rp++, dp++)
+ {
+ *dp = *rp;
+ }
+
+ for (lp = png_ptr->row_buf + 1; i < row_bytes;
+ i++, rp++, lp++, dp++)
+ {
+ *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+ }
+}
+
+static size_t /* PRIVATE */
+png_setup_up_row(png_structrp png_ptr, size_t row_bytes, size_t lmins)
{
png_bytep rp, dp, pp;
- png_size_t i;
- png_size_t sum = 0;
- int v;
+ size_t i;
+ size_t sum = 0;
+ unsigned int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_UP;
i++, rp++, pp++, dp++)
{
v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
if (sum > lmins) /* We are already worse, don't continue. */
break;
return (sum);
}
+static void /* PRIVATE */
+png_setup_up_row_only(png_structrp png_ptr, size_t row_bytes)
+{
+ png_bytep rp, dp, pp;
+ size_t i;
+
+ png_ptr->try_row[0] = PNG_FILTER_VALUE_UP;
-static png_size_t /* PRIVATE */
-png_setup_avg_row(png_structrp png_ptr, const png_uint_32 bpp,
- const png_size_t row_bytes, const png_size_t lmins)
+ for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
+ pp = png_ptr->prev_row + 1; i < row_bytes;
+ i++, rp++, pp++, dp++)
+ {
+ *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
+ }
+}
+
+static size_t /* PRIVATE */
+png_setup_avg_row(png_structrp png_ptr, png_uint_32 bpp,
+ size_t row_bytes, size_t lmins)
{
png_bytep rp, dp, pp, lp;
png_uint_32 i;
- png_size_t sum = 0;
- int v;
+ size_t sum = 0;
+ unsigned int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_AVG;
for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
- pp = png_ptr->prev_row + 1; i < bpp; i++)
+ pp = png_ptr->prev_row + 1; i < bpp; i++)
{
v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
}
for (lp = png_ptr->row_buf + 1; i < row_bytes; i++)
v = *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
& 0xff);
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
if (sum > lmins) /* We are already worse, don't continue. */
break;
return (sum);
}
+static void /* PRIVATE */
+png_setup_avg_row_only(png_structrp png_ptr, png_uint_32 bpp,
+ size_t row_bytes)
+{
+ png_bytep rp, dp, pp, lp;
+ png_uint_32 i;
+
+ png_ptr->try_row[0] = PNG_FILTER_VALUE_AVG;
+
+ for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
+ pp = png_ptr->prev_row + 1; i < bpp; i++)
+ {
+ *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+ }
+
+ for (lp = png_ptr->row_buf + 1; i < row_bytes; i++)
+ {
+ *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
+ & 0xff);
+ }
+}
-static png_size_t /* PRIVATE */
-png_setup_paeth_row(png_structrp png_ptr, const png_uint_32 bpp,
- const png_size_t row_bytes, const png_size_t lmins)
+static size_t /* PRIVATE */
+png_setup_paeth_row(png_structrp png_ptr, png_uint_32 bpp,
+ size_t row_bytes, size_t lmins)
{
png_bytep rp, dp, pp, cp, lp;
- png_size_t i;
- png_size_t sum = 0;
- int v;
+ size_t i;
+ size_t sum = 0;
+ unsigned int v;
png_ptr->try_row[0] = PNG_FILTER_VALUE_PAETH;
{
v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
}
for (lp = png_ptr->row_buf + 1, cp = png_ptr->prev_row + 1; i < row_bytes;
v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
if (sum > lmins) /* We are already worse, don't continue. */
break;
return (sum);
}
+static void /* PRIVATE */
+png_setup_paeth_row_only(png_structrp png_ptr, png_uint_32 bpp,
+ size_t row_bytes)
+{
+ png_bytep rp, dp, pp, cp, lp;
+ size_t i;
+
+ png_ptr->try_row[0] = PNG_FILTER_VALUE_PAETH;
+
+ for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
+ pp = png_ptr->prev_row + 1; i < bpp; i++)
+ {
+ *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+ }
+
+ for (lp = png_ptr->row_buf + 1, cp = png_ptr->prev_row + 1; i < row_bytes;
+ i++)
+ {
+ int a, b, c, pa, pb, pc, p;
+
+ b = *pp++;
+ c = *cp++;
+ a = *lp++;
+
+ p = b - c;
+ pc = a - c;
+
+#ifdef PNG_USE_ABS
+ pa = abs(p);
+ pb = abs(pc);
+ pc = abs(p + pc);
+#else
+ pa = p < 0 ? -p : p;
+ pb = pc < 0 ? -pc : pc;
+ pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+ p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+ *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+ }
+}
#endif /* WRITE_FILTER */
void /* PRIVATE */
#ifndef PNG_WRITE_FILTER_SUPPORTED
png_write_filtered_row(png_ptr, png_ptr->row_buf, row_info->rowbytes+1);
#else
- png_byte filter_to_do = png_ptr->do_filter;
+ unsigned int filter_to_do = png_ptr->do_filter;
png_bytep row_buf;
png_bytep best_row;
png_uint_32 bpp;
- png_size_t mins;
- png_size_t row_bytes = row_info->rowbytes;
+ size_t mins;
+ size_t row_bytes = row_info->rowbytes;
png_debug(1, "in png_write_find_filter");
*/
best_row = png_ptr->row_buf;
-
- if ((filter_to_do & PNG_FILTER_NONE) != 0 && filter_to_do != PNG_FILTER_NONE)
+ if (PNG_SIZE_MAX/128 <= row_bytes)
{
+ /* Overflow can occur in the calculation, just select the lowest set
+ * filter.
+ */
+ filter_to_do &= 0U-filter_to_do;
+ }
+ else if ((filter_to_do & PNG_FILTER_NONE) != 0 &&
+ filter_to_do != PNG_FILTER_NONE)
+ {
+ /* Overflow not possible and multiple filters in the list, including the
+ * 'none' filter.
+ */
png_bytep rp;
- png_size_t sum = 0;
- png_size_t i;
- int v;
+ size_t sum = 0;
+ size_t i;
+ unsigned int v;
- if (PNG_SIZE_MAX/128 <= row_bytes)
- {
- for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
- {
- /* Check for overflow */
- if (sum > PNG_SIZE_MAX/128 - 256)
- break;
-
- v = *rp;
- sum += (v < 128) ? v : 256 - v;
- }
- }
- else /* Overflow is not possible */
{
for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
{
v = *rp;
+#ifdef PNG_USE_ABS
+ sum += 128 - abs((int)v - 128);
+#else
sum += (v < 128) ? v : 256 - v;
+#endif
}
}
if (filter_to_do == PNG_FILTER_SUB)
/* It's the only filter so no testing is needed */
{
- (void) png_setup_sub_row(png_ptr, bpp, row_bytes, mins);
+ png_setup_sub_row_only(png_ptr, bpp, row_bytes);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_SUB) != 0)
{
- png_size_t sum;
- png_size_t lmins = mins;
+ size_t sum;
+ size_t lmins = mins;
sum = png_setup_sub_row(png_ptr, bpp, row_bytes, lmins);
/* Up filter */
if (filter_to_do == PNG_FILTER_UP)
{
- (void) png_setup_up_row(png_ptr, row_bytes, mins);
+ png_setup_up_row_only(png_ptr, row_bytes);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_UP) != 0)
{
- png_size_t sum;
- png_size_t lmins = mins;
+ size_t sum;
+ size_t lmins = mins;
sum = png_setup_up_row(png_ptr, row_bytes, lmins);
/* Avg filter */
if (filter_to_do == PNG_FILTER_AVG)
{
- (void) png_setup_avg_row(png_ptr, bpp, row_bytes, mins);
+ png_setup_avg_row_only(png_ptr, bpp, row_bytes);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_AVG) != 0)
{
- png_size_t sum;
- png_size_t lmins = mins;
+ size_t sum;
+ size_t lmins = mins;
sum= png_setup_avg_row(png_ptr, bpp, row_bytes, lmins);
}
/* Paeth filter */
- if ((filter_to_do == PNG_FILTER_PAETH) != 0)
+ if (filter_to_do == PNG_FILTER_PAETH)
{
- (void) png_setup_paeth_row(png_ptr, bpp, row_bytes, mins);
+ png_setup_paeth_row_only(png_ptr, bpp, row_bytes);
best_row = png_ptr->try_row;
}
else if ((filter_to_do & PNG_FILTER_PAETH) != 0)
{
- png_size_t sum;
- png_size_t lmins = mins;
+ size_t sum;
+ size_t lmins = mins;
sum = png_setup_paeth_row(png_ptr, bpp, row_bytes, lmins);
/* Do the actual writing of a previously filtered row. */
static void
png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
- png_size_t full_row_length/*includes filter byte*/)
+ size_t full_row_length/*includes filter byte*/)
{
png_debug(1, "in png_write_filtered_row");