diff options
Diffstat (limited to 'src/3rdparty/libpng/pngwutil.c')
| -rw-r--r-- | src/3rdparty/libpng/pngwutil.c | 860 |
1 files changed, 269 insertions, 591 deletions
diff --git a/src/3rdparty/libpng/pngwutil.c b/src/3rdparty/libpng/pngwutil.c index b289671d12..adc4729c24 100644 --- a/src/3rdparty/libpng/pngwutil.c +++ b/src/3rdparty/libpng/pngwutil.c @@ -1,7 +1,7 @@ /* pngwutil.c - utilities to write a PNG file * - * Last changed in libpng 1.6.17 [March 26, 2015] + * Last changed in libpng 1.6.19 [November 12, 2015] * Copyright (c) 1998-2015 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.) @@ -179,7 +179,7 @@ png_write_complete_chunk(png_structrp png_ptr, png_uint_32 chunk_name, if (png_ptr == NULL) return; - /* On 64 bit architectures 'length' may not fit in a png_uint_32. */ + /* On 64-bit architectures 'length' may not fit in a png_uint_32. */ if (length > PNG_UINT_31_MAX) png_error(png_ptr, "length exceeds PNG maximum"); @@ -308,7 +308,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner, */ (void)png_safecat(msg, (sizeof msg), 10, " using zstream"); #endif -#if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC +#if PNG_RELEASE_BUILD png_warning(png_ptr, msg); /* Attempt sane error recovery */ @@ -922,17 +922,20 @@ void /* PRIVATE */ png_write_PLTE(png_structrp png_ptr, png_const_colorp palette, png_uint_32 num_pal) { - png_uint_32 i; + png_uint_32 max_palette_length, i; png_const_colorp pal_ptr; png_byte buf[3]; png_debug(1, "in png_write_PLTE"); + max_palette_length = (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ? + (1 << png_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH; + if (( #ifdef PNG_MNG_FEATURES_SUPPORTED (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 && #endif - num_pal == 0) || num_pal > 256) + num_pal == 0) || num_pal > max_palette_length) { if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) { @@ -1444,7 +1447,7 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha, else if (color_type == PNG_COLOR_TYPE_GRAY) { - /* One 16 bit value */ + /* One 16-bit value */ if (tran->gray >= (1 << png_ptr->bit_depth)) { png_app_warning(png_ptr, @@ -1459,7 +1462,7 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha, else if (color_type == PNG_COLOR_TYPE_RGB) { - /* Three 16 bit values */ + /* Three 16-bit values */ png_save_uint_16(buf, tran->red); png_save_uint_16(buf + 2, tran->green); png_save_uint_16(buf + 4, tran->blue); @@ -1961,6 +1964,10 @@ png_write_start_row(png_structrp png_ptr) png_alloc_size_t buf_size; int usr_pixel_depth; +#ifdef PNG_WRITE_FILTER_SUPPORTED + png_byte filters; +#endif + png_debug(1, "in png_write_start_row"); usr_pixel_depth = png_ptr->usr_channels * png_ptr->usr_bit_depth; @@ -1971,50 +1978,54 @@ png_write_start_row(png_structrp png_ptr) png_ptr->maximum_pixel_depth = (png_byte)usr_pixel_depth; /* Set up row buffer */ - png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, buf_size); + png_ptr->row_buf = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size)); png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE; #ifdef PNG_WRITE_FILTER_SUPPORTED - /* Set up filtering buffer, if using this filter */ - if (png_ptr->do_filter & PNG_FILTER_SUB) - { - png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, png_ptr->rowbytes + 1); + filters = png_ptr->do_filter; - png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB; - } + if (png_ptr->height == 1) + filters &= 0xff & ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH); + + if (png_ptr->width == 1) + filters &= 0xff & ~(PNG_FILTER_SUB|PNG_FILTER_AVG|PNG_FILTER_PAETH); + + if (filters == 0) + filters = PNG_FILTER_NONE; - /* We only need to keep the previous row if we are using one of these. */ - if ((png_ptr->do_filter & - (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) != 0) + png_ptr->do_filter = filters; + + if (((filters & (PNG_FILTER_SUB | PNG_FILTER_UP | PNG_FILTER_AVG | + PNG_FILTER_PAETH)) != 0) && png_ptr->try_row == NULL) { - /* Set up previous row buffer */ - png_ptr->prev_row = (png_bytep)png_calloc(png_ptr, buf_size); + int num_filters = 0; - if ((png_ptr->do_filter & PNG_FILTER_UP) != 0) - { - png_ptr->up_row = (png_bytep)png_malloc(png_ptr, - png_ptr->rowbytes + 1); + png_ptr->try_row = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size)); - png_ptr->up_row[0] = PNG_FILTER_VALUE_UP; - } + if (filters & PNG_FILTER_SUB) + num_filters++; - if ((png_ptr->do_filter & PNG_FILTER_AVG) != 0) - { - png_ptr->avg_row = (png_bytep)png_malloc(png_ptr, - png_ptr->rowbytes + 1); + if (filters & PNG_FILTER_UP) + num_filters++; - png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG; - } + if (filters & PNG_FILTER_AVG) + num_filters++; - if ((png_ptr->do_filter & PNG_FILTER_PAETH) != 0) - { - png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr, - png_ptr->rowbytes + 1); + if (filters & PNG_FILTER_PAETH) + num_filters++; - png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH; - } + if (num_filters > 1) + png_ptr->tst_row = png_voidcast(png_bytep, png_malloc(png_ptr, + buf_size)); } + + /* We only need to keep the previous row if we are using one of the following + * filters. + */ + 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)); #endif /* WRITE_FILTER */ #ifdef PNG_WRITE_INTERLACING_SUPPORTED @@ -2160,7 +2171,7 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) { png_bytep sp; png_bytep dp; - int shift; + unsigned int shift; int d; int value; png_uint_32 i; @@ -2198,7 +2209,7 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) { png_bytep sp; png_bytep dp; - int shift; + unsigned int shift; int d; int value; png_uint_32 i; @@ -2235,7 +2246,7 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) { png_bytep sp; png_bytep dp; - int shift; + unsigned int shift; int d; int value; png_uint_32 i; @@ -2310,6 +2321,7 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) } #endif + /* This filters the row, chooses which filter to use, if it has not already * been specified by the application, and then writes the row out with the * chosen filter. @@ -2318,42 +2330,172 @@ static void /* PRIVATE */ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row, png_size_t row_bytes); -#define PNG_MAXSUM (((png_uint_32)(-1)) >> 1) -#define PNG_HISHIFT 10 -#define PNG_LOMASK ((png_uint_32)0xffffL) -#define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT)) +#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) +{ + png_bytep rp, dp, lp; + png_size_t i; + png_size_t sum = 0; + int v; + + 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++) + { + v = *dp = *rp; + sum += (v < 128) ? v : 256 - v; + } + + for (lp = png_ptr->row_buf + 1; i < row_bytes; + i++, rp++, lp++, dp++) + { + v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff); + sum += (v < 128) ? v : 256 - v; + + 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) +{ + png_bytep rp, dp, pp; + png_size_t i; + png_size_t sum = 0; + int v; + + png_ptr->try_row[0] = PNG_FILTER_VALUE_UP; + + 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++) + { + v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff); + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + + return (sum); +} + +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) +{ + png_bytep rp, dp, pp, lp; + png_uint_32 i; + png_size_t sum = 0; + 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++) + { + v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff); + + sum += (v < 128) ? v : 256 - v; + } + + for (lp = png_ptr->row_buf + 1; i < row_bytes; i++) + { + v = *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) + & 0xff); + + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + + return (sum); +} + +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) +{ + png_bytep rp, dp, pp, cp, lp; + png_size_t i; + png_size_t sum = 0; + int v; + + 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++) + { + v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); + + sum += (v < 128) ? v : 256 - v; + } + + 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; + + v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff); + + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + + return (sum); +} +#endif /* WRITE_FILTER */ + void /* PRIVATE */ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info) { - png_bytep best_row; -#ifdef PNG_WRITE_FILTER_SUPPORTED - png_bytep prev_row, row_buf; - png_uint_32 mins, bpp; +#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; + png_bytep row_buf; + png_bytep best_row; + png_uint_32 bpp; + png_size_t mins; png_size_t row_bytes = row_info->rowbytes; -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - int num_p_filters = png_ptr->num_prev_filters; -#endif png_debug(1, "in png_write_find_filter"); -#ifndef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->row_number == 0 && filter_to_do == PNG_ALL_FILTERS) - { - /* These will never be selected so we need not test them. */ - filter_to_do &= ~(PNG_FILTER_UP | PNG_FILTER_PAETH); - } -#endif - /* Find out how many bytes offset each pixel is */ bpp = (row_info->pixel_depth + 7) >> 3; - prev_row = png_ptr->prev_row; -#endif - best_row = png_ptr->row_buf; -#ifdef PNG_WRITE_FILTER_SUPPORTED - row_buf = best_row; - mins = PNG_MAXSUM; + row_buf = png_ptr->row_buf; + mins = PNG_SIZE_MAX - 256/* so we can detect potential overflow of the + running sum */; /* The prediction method we use is to find which method provides the * smallest value when summing the absolute values of the distances @@ -2383,57 +2525,37 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info) /* We don't need to test the 'no filter' case if this is the only filter * that has been chosen, as it doesn't actually do anything to the data. */ + best_row = png_ptr->row_buf; + + if ((filter_to_do & PNG_FILTER_NONE) != 0 && filter_to_do != PNG_FILTER_NONE) { png_bytep rp; - png_uint_32 sum = 0; + png_size_t sum = 0; png_size_t i; int v; - for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++) + if (PNG_SIZE_MAX/128 <= row_bytes) { - v = *rp; - sum += (v < 128) ? v : 256 - v; - } + for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++) + { + /* Check for overflow */ + if (sum > PNG_SIZE_MAX/128 - 256) + break; -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + v = *rp; + sum += (v < 128) ? v : 256 - v; + } + } + else /* Overflow is not possible */ { - png_uint_32 sumhi, sumlo; - int j; - sumlo = sum & PNG_LOMASK; - sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */ - - /* Reduce the sum if we match any of the previous rows */ - for (j = 0; j < num_p_filters; j++) + for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++) { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE) - { - sumlo = (sumlo * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - sumhi = (sumhi * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } + v = *rp; + sum += (v < 128) ? v : 256 - v; } - - /* Factor in the cost of this filter (this is here for completeness, - * but it makes no sense to have a "cost" for the NONE filter, as - * it has the minimum possible computational cost - none). - */ - sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >> - PNG_COST_SHIFT; - - sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >> - PNG_COST_SHIFT; - - if (sumhi > PNG_HIMASK) - sum = PNG_MAXSUM; - - else - sum = (sumhi << PNG_HISHIFT) + sumlo; } -#endif + mins = sum; } @@ -2441,553 +2563,109 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info) if (filter_to_do == PNG_FILTER_SUB) /* It's the only filter so no testing is needed */ { - png_bytep rp, lp, dp; - png_size_t i; - - for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp; - i++, rp++, dp++) - { - *dp = *rp; - } - - for (lp = row_buf + 1; i < row_bytes; - i++, rp++, lp++, dp++) - { - *dp = (png_byte)((int)*rp - (int)*lp); - } - - best_row = png_ptr->sub_row; + (void) png_setup_sub_row(png_ptr, bpp, row_bytes, mins); + best_row = png_ptr->try_row; } else if ((filter_to_do & PNG_FILTER_SUB) != 0) { - png_bytep rp, dp, lp; - png_uint_32 sum = 0, lmins = mins; - png_size_t i; - int v; - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - /* We temporarily increase the "minimum sum" by the factor we - * would reduce the sum of this filter, so that we can do the - * early exit comparison without scaling the sum each time. - */ - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 lmhi, lmlo; - lmlo = lmins & PNG_LOMASK; - lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB) - { - lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> - PNG_COST_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> - PNG_COST_SHIFT; + png_size_t sum; + png_size_t lmins = mins; - if (lmhi > PNG_HIMASK) - lmins = PNG_MAXSUM; - - else - lmins = (lmhi << PNG_HISHIFT) + lmlo; - } -#endif - - for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp; - i++, rp++, dp++) - { - v = *dp = *rp; - - sum += (v < 128) ? v : 256 - v; - } - - for (lp = row_buf + 1; i < row_bytes; - i++, rp++, lp++, dp++) - { - v = *dp = (png_byte)((int)*rp - (int)*lp); - - sum += (v < 128) ? v : 256 - v; - - if (sum > lmins) /* We are already worse, don't continue. */ - break; - } - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 sumhi, sumlo; - sumlo = sum & PNG_LOMASK; - sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB) - { - sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> - PNG_COST_SHIFT; - - sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> - PNG_COST_SHIFT; - - if (sumhi > PNG_HIMASK) - sum = PNG_MAXSUM; - - else - sum = (sumhi << PNG_HISHIFT) + sumlo; - } -#endif + sum = png_setup_sub_row(png_ptr, bpp, row_bytes, lmins); if (sum < mins) { mins = sum; - best_row = png_ptr->sub_row; + best_row = png_ptr->try_row; + if (png_ptr->tst_row != NULL) + { + png_ptr->try_row = png_ptr->tst_row; + png_ptr->tst_row = best_row; + } } } /* Up filter */ if (filter_to_do == PNG_FILTER_UP) { - png_bytep rp, dp, pp; - png_size_t i; - - for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1, - pp = prev_row + 1; i < row_bytes; - i++, rp++, pp++, dp++) - { - *dp = (png_byte)((int)*rp - (int)*pp); - } - - best_row = png_ptr->up_row; + (void) png_setup_up_row(png_ptr, row_bytes, mins); + best_row = png_ptr->try_row; } else if ((filter_to_do & PNG_FILTER_UP) != 0) { - png_bytep rp, dp, pp; - png_uint_32 sum = 0, lmins = mins; - png_size_t i; - int v; - - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 lmhi, lmlo; - lmlo = lmins & PNG_LOMASK; - lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP) - { - lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >> - PNG_COST_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >> - PNG_COST_SHIFT; - - if (lmhi > PNG_HIMASK) - lmins = PNG_MAXSUM; - - else - lmins = (lmhi << PNG_HISHIFT) + lmlo; - } -#endif - - for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1, - pp = prev_row + 1; i < row_bytes; i++) - { - v = *dp++ = (png_byte)((int)*rp++ - (int)*pp++); + png_size_t sum; + png_size_t lmins = mins; - sum += (v < 128) ? v : 256 - v; - - if (sum > lmins) /* We are already worse, don't continue. */ - break; - } - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 sumhi, sumlo; - sumlo = sum & PNG_LOMASK; - sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP) - { - sumlo = (sumlo * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - sumhi = (sumhi * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >> - PNG_COST_SHIFT; - - sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >> - PNG_COST_SHIFT; - - if (sumhi > PNG_HIMASK) - sum = PNG_MAXSUM; - - else - sum = (sumhi << PNG_HISHIFT) + sumlo; - } -#endif + sum = png_setup_up_row(png_ptr, row_bytes, lmins); if (sum < mins) { mins = sum; - best_row = png_ptr->up_row; + best_row = png_ptr->try_row; + if (png_ptr->tst_row != NULL) + { + png_ptr->try_row = png_ptr->tst_row; + png_ptr->tst_row = best_row; + } } } /* Avg filter */ if (filter_to_do == PNG_FILTER_AVG) { - png_bytep rp, dp, pp, lp; - png_uint_32 i; - - for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1, - pp = prev_row + 1; i < bpp; i++) - { - *dp++ = (png_byte)((int)*rp++ - ((int)*pp++ / 2)); - } - - for (lp = row_buf + 1; i < row_bytes; i++) - { - *dp++ = - (png_byte)((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)); - } - best_row = png_ptr->avg_row; + (void) png_setup_avg_row(png_ptr, bpp, row_bytes, mins); + best_row = png_ptr->try_row; } else if ((filter_to_do & PNG_FILTER_AVG) != 0) { - png_bytep rp, dp, pp, lp; - png_uint_32 sum = 0, lmins = mins; - png_size_t i; - int v; - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 lmhi, lmlo; - lmlo = lmins & PNG_LOMASK; - lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG) - { - lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >> - PNG_COST_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >> - PNG_COST_SHIFT; - - if (lmhi > PNG_HIMASK) - lmins = PNG_MAXSUM; - - else - lmins = (lmhi << PNG_HISHIFT) + lmlo; - } -#endif - - for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1, - pp = prev_row + 1; i < bpp; i++) - { - v = *dp++ = (png_byte)((int)*rp++ - ((int)*pp++ / 2)); - - sum += (v < 128) ? v : 256 - v; - } - - for (lp = row_buf + 1; i < row_bytes; i++) - { - v = *dp++ = - (png_byte)(((int)*rp++ - ((int)*pp++ + (int)*lp++) / 2)); - - sum += (v < 128) ? v : 256 - v; - - if (sum > lmins) /* We are already worse, don't continue. */ - break; - } - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 sumhi, sumlo; - sumlo = sum & PNG_LOMASK; - sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE) - { - sumlo = (sumlo * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - sumhi = (sumhi * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >> - PNG_COST_SHIFT; + png_size_t sum; + png_size_t lmins = mins; - sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >> - PNG_COST_SHIFT; - - if (sumhi > PNG_HIMASK) - sum = PNG_MAXSUM; - - else - sum = (sumhi << PNG_HISHIFT) + sumlo; - } -#endif + sum= png_setup_avg_row(png_ptr, bpp, row_bytes, lmins); if (sum < mins) { mins = sum; - best_row = png_ptr->avg_row; + best_row = png_ptr->try_row; + if (png_ptr->tst_row != NULL) + { + png_ptr->try_row = png_ptr->tst_row; + png_ptr->tst_row = best_row; + } } } /* Paeth filter */ if ((filter_to_do == PNG_FILTER_PAETH) != 0) { - png_bytep rp, dp, pp, cp, lp; - png_size_t i; - - for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1, - pp = prev_row + 1; i < bpp; i++) - { - *dp++ = (png_byte)((int)*rp++ - (int)*pp++); - } - - for (lp = row_buf + 1, cp = 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); - } - best_row = png_ptr->paeth_row; + (void) png_setup_paeth_row(png_ptr, bpp, row_bytes, mins); + best_row = png_ptr->try_row; } else if ((filter_to_do & PNG_FILTER_PAETH) != 0) { - png_bytep rp, dp, pp, cp, lp; - png_uint_32 sum = 0, lmins = mins; - png_size_t i; - int v; - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) - { - int j; - png_uint_32 lmhi, lmlo; - lmlo = lmins & PNG_LOMASK; - lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) - { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH) - { - lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } - } - - lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >> - PNG_COST_SHIFT; - - lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >> - PNG_COST_SHIFT; - - if (lmhi > PNG_HIMASK) - lmins = PNG_MAXSUM; - - else - lmins = (lmhi << PNG_HISHIFT) + lmlo; - } -#endif - - for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1, - pp = prev_row + 1; i < bpp; i++) - { - v = *dp++ = (png_byte)((int)*rp++ - (int)*pp++); + png_size_t sum; + png_size_t lmins = mins; - sum += (v < 128) ? v : 256 - v; - } - - for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++) - { - int a, b, c, pa, pb, pc, p; + sum = png_setup_paeth_row(png_ptr, bpp, row_bytes, lmins); - b = *pp++; - c = *cp++; - a = *lp++; - -#ifndef PNG_SLOW_PAETH - 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; -#else /* SLOW_PAETH */ - p = a + b - c; - pa = abs(p - a); - pb = abs(p - b); - pc = abs(p - c); - - if (pa <= pb && pa <= pc) - p = a; - - else if (pb <= pc) - p = b; - - else - p = c; -#endif /* SLOW_PAETH */ - - v = *dp++ = (png_byte)((int)*rp++ - p); - - sum += (v < 128) ? v : 256 - v; - - if (sum > lmins) /* We are already worse, don't continue. */ - break; - } - -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + if (sum < mins) { - int j; - png_uint_32 sumhi, sumlo; - sumlo = sum & PNG_LOMASK; - sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; - - for (j = 0; j < num_p_filters; j++) + best_row = png_ptr->try_row; + if (png_ptr->tst_row != NULL) { - if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH) - { - sumlo = (sumlo * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - - sumhi = (sumhi * png_ptr->filter_weights[j]) >> - PNG_WEIGHT_SHIFT; - } + png_ptr->try_row = png_ptr->tst_row; + png_ptr->tst_row = best_row; } - - sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >> - PNG_COST_SHIFT; - - sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >> - PNG_COST_SHIFT; - - if (sumhi > PNG_HIMASK) - sum = PNG_MAXSUM; - - else - sum = (sumhi << PNG_HISHIFT) + sumlo; - } -#endif - - if (sum < mins) - { - best_row = png_ptr->paeth_row; } } -#endif /* WRITE_FILTER */ /* Do the actual writing of the filtered row data from the chosen filter. */ png_write_filtered_row(png_ptr, best_row, row_info->rowbytes+1); -#ifdef PNG_WRITE_FILTER_SUPPORTED -#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED - /* Save the type of filter we picked this time for future calculations */ - if (png_ptr->num_prev_filters > 0) - { - int j; - - for (j = 1; j < num_p_filters; j++) - { - png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1]; - } - - png_ptr->prev_filters[j] = best_row[0]; - } -#endif #endif /* WRITE_FILTER */ } |