Index: third_party/libpng/pngwtran.c |
diff --git a/third_party/libpng/pngwtran.c b/third_party/libpng/pngwtran.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..038a2ef5dcd5a7c5f97c3b0bf3cbe1b0305d9fab |
--- /dev/null |
+++ b/third_party/libpng/pngwtran.c |
@@ -0,0 +1,576 @@ |
+ |
+/* pngwtran.c - transforms the data in a row for PNG writers |
+ * |
+ * Last changed in libpng 1.6.18 [July 23, 2015] |
+ * 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.) |
+ * |
+ * This code is released under the libpng license. |
+ * For conditions of distribution and use, see the disclaimer |
+ * and license in png.h |
+ */ |
+ |
+#include "pngpriv.h" |
+ |
+#ifdef PNG_WRITE_SUPPORTED |
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED |
+ |
+#ifdef PNG_WRITE_PACK_SUPPORTED |
+/* Pack pixels into bytes. Pass the true bit depth in bit_depth. The |
+ * row_info bit depth should be 8 (one pixel per byte). The channels |
+ * should be 1 (this only happens on grayscale and paletted images). |
+ */ |
+static void |
+png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth) |
+{ |
+ png_debug(1, "in png_do_pack"); |
+ |
+ if (row_info->bit_depth == 8 && |
+ row_info->channels == 1) |
+ { |
+ switch ((int)bit_depth) |
+ { |
+ case 1: |
+ { |
+ png_bytep sp, dp; |
+ int mask, v; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ sp = row; |
+ dp = row; |
+ mask = 0x80; |
+ v = 0; |
+ |
+ for (i = 0; i < row_width; i++) |
+ { |
+ if (*sp != 0) |
+ v |= mask; |
+ |
+ sp++; |
+ |
+ if (mask > 1) |
+ mask >>= 1; |
+ |
+ else |
+ { |
+ mask = 0x80; |
+ *dp = (png_byte)v; |
+ dp++; |
+ v = 0; |
+ } |
+ } |
+ |
+ if (mask != 0x80) |
+ *dp = (png_byte)v; |
+ |
+ break; |
+ } |
+ |
+ case 2: |
+ { |
+ png_bytep sp, dp; |
+ unsigned int shift; |
+ int v; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ sp = row; |
+ dp = row; |
+ shift = 6; |
+ v = 0; |
+ |
+ for (i = 0; i < row_width; i++) |
+ { |
+ png_byte value; |
+ |
+ value = (png_byte)(*sp & 0x03); |
+ v |= (value << shift); |
+ |
+ if (shift == 0) |
+ { |
+ shift = 6; |
+ *dp = (png_byte)v; |
+ dp++; |
+ v = 0; |
+ } |
+ |
+ else |
+ shift -= 2; |
+ |
+ sp++; |
+ } |
+ |
+ if (shift != 6) |
+ *dp = (png_byte)v; |
+ |
+ break; |
+ } |
+ |
+ case 4: |
+ { |
+ png_bytep sp, dp; |
+ unsigned int shift; |
+ int v; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ sp = row; |
+ dp = row; |
+ shift = 4; |
+ v = 0; |
+ |
+ for (i = 0; i < row_width; i++) |
+ { |
+ png_byte value; |
+ |
+ value = (png_byte)(*sp & 0x0f); |
+ v |= (value << shift); |
+ |
+ if (shift == 0) |
+ { |
+ shift = 4; |
+ *dp = (png_byte)v; |
+ dp++; |
+ v = 0; |
+ } |
+ |
+ else |
+ shift -= 4; |
+ |
+ sp++; |
+ } |
+ |
+ if (shift != 4) |
+ *dp = (png_byte)v; |
+ |
+ break; |
+ } |
+ |
+ default: |
+ break; |
+ } |
+ |
+ row_info->bit_depth = (png_byte)bit_depth; |
+ row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels); |
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, |
+ row_info->width); |
+ } |
+} |
+#endif |
+ |
+#ifdef PNG_WRITE_SHIFT_SUPPORTED |
+/* Shift pixel values to take advantage of whole range. Pass the |
+ * true number of bits in bit_depth. The row should be packed |
+ * according to row_info->bit_depth. Thus, if you had a row of |
+ * bit depth 4, but the pixels only had values from 0 to 7, you |
+ * would pass 3 as bit_depth, and this routine would translate the |
+ * data to 0 to 15. |
+ */ |
+static void |
+png_do_shift(png_row_infop row_info, png_bytep row, |
+ png_const_color_8p bit_depth) |
+{ |
+ png_debug(1, "in png_do_shift"); |
+ |
+ if (row_info->color_type != PNG_COLOR_TYPE_PALETTE) |
+ { |
+ int shift_start[4], shift_dec[4]; |
+ int channels = 0; |
+ |
+ if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0) |
+ { |
+ shift_start[channels] = row_info->bit_depth - bit_depth->red; |
+ shift_dec[channels] = bit_depth->red; |
+ channels++; |
+ |
+ shift_start[channels] = row_info->bit_depth - bit_depth->green; |
+ shift_dec[channels] = bit_depth->green; |
+ channels++; |
+ |
+ shift_start[channels] = row_info->bit_depth - bit_depth->blue; |
+ shift_dec[channels] = bit_depth->blue; |
+ channels++; |
+ } |
+ |
+ else |
+ { |
+ shift_start[channels] = row_info->bit_depth - bit_depth->gray; |
+ shift_dec[channels] = bit_depth->gray; |
+ channels++; |
+ } |
+ |
+ if ((row_info->color_type & PNG_COLOR_MASK_ALPHA) != 0) |
+ { |
+ shift_start[channels] = row_info->bit_depth - bit_depth->alpha; |
+ shift_dec[channels] = bit_depth->alpha; |
+ channels++; |
+ } |
+ |
+ /* With low row depths, could only be grayscale, so one channel */ |
+ if (row_info->bit_depth < 8) |
+ { |
+ png_bytep bp = row; |
+ png_size_t i; |
+ unsigned int mask; |
+ png_size_t row_bytes = row_info->rowbytes; |
+ |
+ if (bit_depth->gray == 1 && row_info->bit_depth == 2) |
+ mask = 0x55; |
+ |
+ else if (row_info->bit_depth == 4 && bit_depth->gray == 3) |
+ mask = 0x11; |
+ |
+ else |
+ mask = 0xff; |
+ |
+ for (i = 0; i < row_bytes; i++, bp++) |
+ { |
+ int j; |
+ unsigned int v, out; |
+ |
+ v = *bp; |
+ out = 0; |
+ |
+ for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) |
+ { |
+ if (j > 0) |
+ out |= v << j; |
+ |
+ else |
+ out |= (v >> (-j)) & mask; |
+ } |
+ |
+ *bp = (png_byte)(out & 0xff); |
+ } |
+ } |
+ |
+ else if (row_info->bit_depth == 8) |
+ { |
+ png_bytep bp = row; |
+ png_uint_32 i; |
+ png_uint_32 istop = channels * row_info->width; |
+ |
+ for (i = 0; i < istop; i++, bp++) |
+ { |
+ |
+ const unsigned int c = i%channels; |
+ int j; |
+ unsigned int v, out; |
+ |
+ v = *bp; |
+ out = 0; |
+ |
+ for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) |
+ { |
+ if (j > 0) |
+ out |= v << j; |
+ |
+ else |
+ out |= v >> (-j); |
+ } |
+ |
+ *bp = (png_byte)(out & 0xff); |
+ } |
+ } |
+ |
+ else |
+ { |
+ png_bytep bp; |
+ png_uint_32 i; |
+ png_uint_32 istop = channels * row_info->width; |
+ |
+ for (bp = row, i = 0; i < istop; i++) |
+ { |
+ const unsigned int c = i%channels; |
+ int j; |
+ unsigned int value, v; |
+ |
+ 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 |= v << j; |
+ |
+ else |
+ value |= v >> (-j); |
+ } |
+ *bp++ = (png_byte)((value >> 8) & 0xff); |
+ *bp++ = (png_byte)(value & 0xff); |
+ } |
+ } |
+ } |
+} |
+#endif |
+ |
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED |
+static void |
+png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) |
+{ |
+ png_debug(1, "in png_do_write_swap_alpha"); |
+ |
+ { |
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
+ { |
+ if (row_info->bit_depth == 8) |
+ { |
+ /* This converts from ARGB to RGBA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ png_byte save = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = save; |
+ } |
+ } |
+ |
+#ifdef PNG_WRITE_16BIT_SUPPORTED |
+ else |
+ { |
+ /* This converts from AARRGGBB to RRGGBBAA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ png_byte save[2]; |
+ save[0] = *(sp++); |
+ save[1] = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = save[0]; |
+ *(dp++) = save[1]; |
+ } |
+ } |
+#endif /* WRITE_16BIT */ |
+ } |
+ |
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
+ { |
+ if (row_info->bit_depth == 8) |
+ { |
+ /* This converts from AG to GA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ png_byte save = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = save; |
+ } |
+ } |
+ |
+#ifdef PNG_WRITE_16BIT_SUPPORTED |
+ else |
+ { |
+ /* This converts from AAGG to GGAA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ png_byte save[2]; |
+ save[0] = *(sp++); |
+ save[1] = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = save[0]; |
+ *(dp++) = save[1]; |
+ } |
+ } |
+#endif /* WRITE_16BIT */ |
+ } |
+ } |
+} |
+#endif |
+ |
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED |
+static void |
+png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) |
+{ |
+ png_debug(1, "in png_do_write_invert_alpha"); |
+ |
+ { |
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
+ { |
+ if (row_info->bit_depth == 8) |
+ { |
+ /* This inverts the alpha channel in RGBA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ /* Does nothing |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ */ |
+ sp+=3; dp = sp; |
+ *dp = (png_byte)(255 - *(sp++)); |
+ } |
+ } |
+ |
+#ifdef PNG_WRITE_16BIT_SUPPORTED |
+ else |
+ { |
+ /* This inverts the alpha channel in RRGGBBAA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ /* Does nothing |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ */ |
+ sp+=6; dp = sp; |
+ *(dp++) = (png_byte)(255 - *(sp++)); |
+ *dp = (png_byte)(255 - *(sp++)); |
+ } |
+ } |
+#endif /* WRITE_16BIT */ |
+ } |
+ |
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
+ { |
+ if (row_info->bit_depth == 8) |
+ { |
+ /* This inverts the alpha channel in GA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ *(dp++) = *(sp++); |
+ *(dp++) = (png_byte)(255 - *(sp++)); |
+ } |
+ } |
+ |
+#ifdef PNG_WRITE_16BIT_SUPPORTED |
+ else |
+ { |
+ /* This inverts the alpha channel in GGAA */ |
+ png_bytep sp, dp; |
+ png_uint_32 i; |
+ png_uint_32 row_width = row_info->width; |
+ |
+ for (i = 0, sp = dp = row; i < row_width; i++) |
+ { |
+ /* Does nothing |
+ *(dp++) = *(sp++); |
+ *(dp++) = *(sp++); |
+ */ |
+ sp+=2; dp = sp; |
+ *(dp++) = (png_byte)(255 - *(sp++)); |
+ *dp = (png_byte)(255 - *(sp++)); |
+ } |
+ } |
+#endif /* WRITE_16BIT */ |
+ } |
+ } |
+} |
+#endif |
+ |
+/* Transform the data according to the user's wishes. The order of |
+ * transformations is significant. |
+ */ |
+void /* PRIVATE */ |
+png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info) |
+{ |
+ png_debug(1, "in png_do_write_transformations"); |
+ |
+ if (png_ptr == NULL) |
+ return; |
+ |
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED |
+ if ((png_ptr->transformations & PNG_USER_TRANSFORM) != 0) |
+ if (png_ptr->write_user_transform_fn != NULL) |
+ (*(png_ptr->write_user_transform_fn)) /* User write transform |
+ function */ |
+ (png_ptr, /* png_ptr */ |
+ row_info, /* row_info: */ |
+ /* png_uint_32 width; width of row */ |
+ /* png_size_t rowbytes; number of bytes in row */ |
+ /* png_byte color_type; color type of pixels */ |
+ /* png_byte bit_depth; bit depth of samples */ |
+ /* png_byte channels; number of channels (1-4) */ |
+ /* png_byte pixel_depth; bits per pixel (depth*channels) */ |
+ png_ptr->row_buf + 1); /* start of pixel data for row */ |
+#endif |
+ |
+#ifdef PNG_WRITE_FILLER_SUPPORTED |
+ if ((png_ptr->transformations & PNG_FILLER) != 0) |
+ png_do_strip_channel(row_info, png_ptr->row_buf + 1, |
+ !(png_ptr->flags & PNG_FLAG_FILLER_AFTER)); |
+#endif |
+ |
+#ifdef PNG_WRITE_PACKSWAP_SUPPORTED |
+ if ((png_ptr->transformations & PNG_PACKSWAP) != 0) |
+ png_do_packswap(row_info, png_ptr->row_buf + 1); |
+#endif |
+ |
+#ifdef PNG_WRITE_PACK_SUPPORTED |
+ if ((png_ptr->transformations & PNG_PACK) != 0) |
+ png_do_pack(row_info, png_ptr->row_buf + 1, |
+ (png_uint_32)png_ptr->bit_depth); |
+#endif |
+ |
+#ifdef PNG_WRITE_SWAP_SUPPORTED |
+# ifdef PNG_16BIT_SUPPORTED |
+ if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0) |
+ png_do_swap(row_info, png_ptr->row_buf + 1); |
+# endif |
+#endif |
+ |
+#ifdef PNG_WRITE_SHIFT_SUPPORTED |
+ if ((png_ptr->transformations & PNG_SHIFT) != 0) |
+ png_do_shift(row_info, png_ptr->row_buf + 1, |
+ &(png_ptr->shift)); |
+#endif |
+ |
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED |
+ if ((png_ptr->transformations & PNG_SWAP_ALPHA) != 0) |
+ png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1); |
+#endif |
+ |
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED |
+ if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0) |
+ png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1); |
+#endif |
+ |
+#ifdef PNG_WRITE_BGR_SUPPORTED |
+ if ((png_ptr->transformations & PNG_BGR) != 0) |
+ png_do_bgr(row_info, png_ptr->row_buf + 1); |
+#endif |
+ |
+#ifdef PNG_WRITE_INVERT_SUPPORTED |
+ if ((png_ptr->transformations & PNG_INVERT_MONO) != 0) |
+ png_do_invert(row_info, png_ptr->row_buf + 1); |
+#endif |
+} |
+#endif /* WRITE_TRANSFORMS */ |
+#endif /* WRITE */ |