From b6788ccaffe586ce9b53964c5708a0bb94e0cbd2 Mon Sep 17 00:00:00 2001 From: John Bowler Date: Mon, 29 Dec 2014 16:31:58 -0600 Subject: [PATCH] [libpng16] Implement previously untested libpng transforms in pngvalid.c --- ANNOUNCE | 1 + CHANGES | 1 + contrib/libtests/pngvalid.c | 734 ++++++++++++++++++++++++++++++++---- 3 files changed, 656 insertions(+), 80 deletions(-) diff --git a/ANNOUNCE b/ANNOUNCE index e7ab7f5ad..cfdc20244 100644 --- a/ANNOUNCE +++ b/ANNOUNCE @@ -32,6 +32,7 @@ Version 1.6.17beta01 [December 29, 2014] png_read_row to skip the unnecessary row de-interlace stuff. Added testing of png_set_packing() to pngvalid.c Regenerated configure scripts in the *.tar distributions with libtool-2.4.4 + Implement previously untested cases of libpng transforms in pngvalid.c Fixed byte order in 2-byte filler, in png_do_read_filler(). Send comments/corrections/commendations to png-mng-implement at lists.sf.net diff --git a/CHANGES b/CHANGES index a0f9606f6..f254347bb 100644 --- a/CHANGES +++ b/CHANGES @@ -5132,6 +5132,7 @@ Version 1.6.17beta01 [December 29, 2014] png_read_row to skip the unnecessary row de-interlace stuff. Added testing of png_set_packing() to pngvalid.c Regenerated configure scripts in the *.tar distributions with libtool-2.4.4 + Implement previously untested cases of libpng transforms in pngvalid.c Fixed byte order in 2-byte filler, in png_do_read_filler(). Send comments/corrections/commendations to png-mng-implement at lists.sf.net diff --git a/contrib/libtests/pngvalid.c b/contrib/libtests/pngvalid.c index 10a14b0d7..7336be031 100644 --- a/contrib/libtests/pngvalid.c +++ b/contrib/libtests/pngvalid.c @@ -278,7 +278,8 @@ random_mod(unsigned int max) return x % max; /* 0 .. max-1 */ } -#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +#if (defined PNG_READ_RGB_TO_GRAY_SUPPORTED) ||\ + (defined PNG_READ_FILLER_SUPPORTED) static int random_choice(void) { @@ -303,7 +304,7 @@ random_choice(void) #define COL_FROM_ID(id) ((png_byte)((id)& 0x7U)) #define DEPTH_FROM_ID(id) ((png_byte)(((id) >> 3) & 0x1fU)) #define PALETTE_FROM_ID(id) (((id) >> 8) & 0x1f) -#define INTERLACE_FROM_ID(id) ((int)(((id) >> 13) & 0x3)) +#define INTERLACE_FROM_ID(id) ((png_byte)(((id) >> 13) & 0x3)) #define DO_INTERLACE_FROM_ID(id) ((int)(((id)>>15) & 1)) #define WIDTH_FROM_ID(id) (((id)>>16) & 0xff) #define HEIGHT_FROM_ID(id) (((id)>>24) & 0xff) @@ -440,7 +441,7 @@ next_format(png_bytep colour_type, png_bytep bit_depth, #ifdef PNG_READ_TRANSFORMS_SUPPORTED static unsigned int sample(png_const_bytep row, png_byte colour_type, png_byte bit_depth, - png_uint_32 x, unsigned int sample_index) + png_uint_32 x, unsigned int sample_index, int swap16, int littleendian) { png_uint_32 bit_index, result; @@ -469,11 +470,23 @@ sample(png_const_bytep row, png_byte colour_type, png_byte bit_depth, return result; else if (bit_depth > 8) - return (result << 8) + *++row; + { + if (swap16) + return (*++row << 8) + result; + else + return (result << 8) + *++row; + } - /* Less than 8 bits per sample. */ + /* Less than 8 bits per sample. By default PNG has the big end of + * the egg on the left of the screen, but if littleendian is set + * then the big end is on the right. + */ bit_index &= 7; - return (result >> (8-bit_index-bit_depth)) & ((1U<> bit_index) & ((1U<pwrite = png_create_write_struct(png_get_libpng_ver(NULL), + ps->pwrite = png_create_write_struct(PNG_LIBPNG_VER_STRING, ps, store_error, store_warning); png_set_write_fn(ps->pwrite, ps, store_write, store_flush); @@ -3172,10 +3185,10 @@ init_standard_palette(png_store *ps, png_structp pp, png_infop pi, int npalette, for (; i<256; ++i) tRNS[i] = 24; -# ifdef PNG_WRITE_tRNS_SUPPORTED +# ifdef PNG_WRITE_tRNS_SUPPORTED if (j > 0) png_set_tRNS(pp, pi, tRNS, j, 0/*color*/); -# endif +# endif } } @@ -4263,7 +4276,8 @@ typedef struct standard_display png_byte green_sBIT; png_byte blue_sBIT; png_byte alpha_sBIT; - int interlace_type; + png_byte interlace_type; + png_byte filler; /* Output has a filler */ png_uint_32 id; /* Calculated file ID */ png_uint_32 w; /* Width of image */ png_uint_32 h; /* Height of image */ @@ -4650,8 +4664,16 @@ standard_info_part2(standard_display *dp, png_const_structp pp, png_const_infop pi, int nImages) { /* Record cbRow now that it can be found. */ - dp->pixel_size = bit_size(pp, png_get_color_type(pp, pi), - png_get_bit_depth(pp, pi)); + { + png_byte ct = png_get_color_type(pp, pi); + png_byte bd = png_get_bit_depth(pp, pi); + + if (bd >= 8 && (ct == PNG_COLOR_TYPE_RGB || ct == PNG_COLOR_TYPE_GRAY) && + dp->filler) + ct |= 4; /* handle filler as faked alpha channel */ + + dp->pixel_size = bit_size(pp, ct, bd); + } dp->bit_width = png_get_image_width(pp, pi) * dp->pixel_size; dp->cbRow = png_get_rowbytes(pp, pi); @@ -5291,10 +5313,17 @@ typedef struct image_pixel */ unsigned int red, green, blue, alpha; /* For non-palette images. */ unsigned int palette_index; /* For a palette image. */ - png_byte colour_type; /* As in the spec. */ - png_byte bit_depth; /* Defines bit size in row */ - png_byte sample_depth; /* Scale of samples */ - int have_tRNS; /* tRNS chunk may need processing */ + png_byte colour_type; /* As in the spec. */ + png_byte bit_depth; /* Defines bit size in row */ + png_byte sample_depth; /* Scale of samples */ + unsigned int have_tRNS :1; /* tRNS chunk may need processing */ + unsigned int swap_rgb :1; /* RGB swapped to BGR */ + unsigned int alpha_first :1; /* Alpha at start, not end */ + unsigned int alpha_inverted :1; /* Alpha channel inverted */ + unsigned int mono_inverted :1; /* Gray channel inverted */ + unsigned int swap16 :1; /* Byte swap 16-bit components */ + unsigned int littleendian :1; /* High bits on right */ + unsigned int sig_bits :1; /* Pixel shifted (sig bits only) */ /* For checking the code calculates double precision floating point values * along with an error value, accumulated from the transforms. Because an @@ -5302,6 +5331,9 @@ typedef struct image_pixel * up to just less than +/-1 in the scaled value) the *lowest* sBIT for each * channel is stored. This sBIT value is folded in to the stored error value * at the end of the application of the transforms to the pixel. + * + * If sig_bits is set above the red, green, blue and alpha values have been + * scaled so they only contain the significant bits of the component values. */ double redf, greenf, bluef, alphaf; double rede, greene, bluee, alphae; @@ -5310,26 +5342,27 @@ typedef struct image_pixel /* Shared utility function, see below. */ static void -image_pixel_setf(image_pixel *this, unsigned int max) +image_pixel_setf(image_pixel *this, unsigned int rMax, unsigned int gMax, + unsigned int bMax, unsigned int aMax) { - this->redf = this->red / (double)max; - this->greenf = this->green / (double)max; - this->bluef = this->blue / (double)max; - this->alphaf = this->alpha / (double)max; + this->redf = this->red / (double)rMax; + this->greenf = this->green / (double)gMax; + this->bluef = this->blue / (double)bMax; + this->alphaf = this->alpha / (double)aMax; - if (this->red < max) + if (this->red < rMax) this->rede = this->redf * DBL_EPSILON; else this->rede = 0; - if (this->green < max) + if (this->green < gMax) this->greene = this->greenf * DBL_EPSILON; else this->greene = 0; - if (this->blue < max) + if (this->blue < bMax) this->bluee = this->bluef * DBL_EPSILON; else this->bluee = 0; - if (this->alpha < max) + if (this->alpha < aMax) this->alphae = this->alphaf * DBL_EPSILON; else this->alphae = 0; @@ -5341,18 +5374,22 @@ image_pixel_setf(image_pixel *this, unsigned int max) */ static void image_pixel_init(image_pixel *this, png_const_bytep row, png_byte colour_type, - png_byte bit_depth, png_uint_32 x, store_palette palette) + png_byte bit_depth, png_uint_32 x, store_palette palette, + PNG_CONST image_pixel *format /*from pngvalid transform of input*/) { PNG_CONST png_byte sample_depth = (png_byte)(colour_type == PNG_COLOR_TYPE_PALETTE ? 8 : bit_depth); PNG_CONST unsigned int max = (1U<swap16); + PNG_CONST int littleendian = (format != 0 && format->littleendian); + PNG_CONST int sig_bits = (format != 0 && format->sig_bits); /* Initially just set everything to the same number and the alpha to opaque. * Note that this currently assumes a simple palette where entry x has colour * rgb(x,x,x)! */ this->palette_index = this->red = this->green = this->blue = - sample(row, colour_type, bit_depth, x, 0); + sample(row, colour_type, bit_depth, x, 0, swap16, littleendian); this->alpha = max; this->red_sBIT = this->green_sBIT = this->blue_sBIT = this->alpha_sBIT = sample_depth; @@ -5376,21 +5413,52 @@ image_pixel_init(image_pixel *this, png_const_bytep row, png_byte colour_type, { unsigned int i = 0; + if ((colour_type & 4) != 0 && format != 0 && format->alpha_first) + { + this->alpha = this->red; + /* This handles the gray case for 'AG' pixels */ + this->palette_index = this->red = this->green = this->blue = + sample(row, colour_type, bit_depth, x, 1, swap16, littleendian); + i = 1; + } + if (colour_type & 2) { - this->green = sample(row, colour_type, bit_depth, x, 1); - this->blue = sample(row, colour_type, bit_depth, x, 2); - i = 2; + /* Green is second for both BGR and RGB: */ + this->green = sample(row, colour_type, bit_depth, x, ++i, swap16, + littleendian); + + if (format != 0 && format->swap_rgb) /* BGR */ + this->red = sample(row, colour_type, bit_depth, x, ++i, swap16, + littleendian); + else + this->blue = sample(row, colour_type, bit_depth, x, ++i, swap16, + littleendian); + } + + else /* grayscale */ if (format != 0 && format->mono_inverted) + this->red = this->green = this->blue = this->red ^ max; + + if ((colour_type & 4) != 0) /* alpha */ + { + if (format == 0 || !format->alpha_first) + this->alpha = sample(row, colour_type, bit_depth, x, ++i, swap16, + littleendian); + + if (format != 0 && format->alpha_inverted) + this->alpha ^= max; } - if (colour_type & 4) - this->alpha = sample(row, colour_type, bit_depth, x, ++i); } /* Calculate the scaled values, these are simply the values divided by * 'max' and the error is initialized to the double precision epsilon value * from the header file. */ - image_pixel_setf(this, max); + image_pixel_setf(this, + sig_bits ? (1U << format->red_sBIT)-1 : max, + sig_bits ? (1U << format->green_sBIT)-1 : max, + sig_bits ? (1U << format->blue_sBIT)-1 : max, + sig_bits ? (1U << format->alpha_sBIT)-1 : max); /* Store the input information for use in the transforms - these will * modify the information. @@ -5399,6 +5467,13 @@ image_pixel_init(image_pixel *this, png_const_bytep row, png_byte colour_type, this->bit_depth = bit_depth; this->sample_depth = sample_depth; this->have_tRNS = 0; + this->swap_rgb = 0; + this->alpha_first = 0; + this->alpha_inverted = 0; + this->mono_inverted = 0; + this->swap16 = 0; + this->littleendian = 0; + this->sig_bits = 0; } /* Convert a palette image to an rgb image. This necessarily converts the tRNS @@ -5636,6 +5711,7 @@ image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that, png_const_structp pp, PNG_CONST transform_display *display) { PNG_CONST unsigned int scale = (1U<sample_depth)-1; + PNG_CONST int sig_bits = that->sig_bits; UNUSED(this) UNUSED(pp) @@ -5650,6 +5726,13 @@ image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that, */ that->red = sample_scale(that->redf, scale); + /* This is a bit bogus; really the above calculation should use the red_sBIT + * value, not sample_depth, but because libpng does png_set_shift by just + * shifting the bits we get errors if we don't do it the same way. + */ + if (sig_bits && that->red_sBIT < that->sample_depth) + that->red >>= that->sample_depth - that->red_sBIT; + /* The error value is increased, at the end, according to the lowest sBIT * value seen. Common sense tells us that the intermediate integer * representations are no more accurate than +/- 0.5 in the integral values, @@ -5665,7 +5748,13 @@ image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that, if (that->colour_type & PNG_COLOR_MASK_COLOR) { that->green = sample_scale(that->greenf, scale); + if (sig_bits && that->green_sBIT < that->sample_depth) + that->green >>= that->sample_depth - that->green_sBIT; + that->blue = sample_scale(that->bluef, scale); + if (sig_bits && that->blue_sBIT < that->sample_depth) + that->blue >>= that->sample_depth - that->blue_sBIT; + that->greene += 1./(2*((1U<green_sBIT)-1)); that->bluee += 1./(2*((1U<blue_sBIT)-1)); } @@ -5685,9 +5774,12 @@ image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that, else { that->alpha = scale; /* opaque */ - that->alpha = 1; /* Override this. */ + that->alphaf = 1; /* Override this. */ that->alphae = 0; /* It's exact ;-) */ } + + if (sig_bits && that->alpha_sBIT < that->sample_depth) + that->alpha >>= that->sample_depth - that->alpha_sBIT; } /* Static 'end' structure: */ @@ -5753,6 +5845,13 @@ transform_info_imp(transform_display *dp, png_structp pp, png_infop pi) dp->output_colour_type = png_get_color_type(pp, pi); dp->output_bit_depth = png_get_bit_depth(pp, pi); + /* If png_set_filler is in action then fake the output color type to include + * an alpha channel where appropriate. + */ + if (dp->output_bit_depth >= 8 && (dp->output_colour_type == PNG_COLOR_TYPE_RGB || + dp->output_colour_type == PNG_COLOR_TYPE_GRAY) && dp->this.filler) + dp->output_colour_type |= 4; + /* Validate the combination of colour type and bit depth that we are getting * out of libpng; the semantics of something not in the PNG spec are, at * best, unclear. @@ -5803,7 +5902,7 @@ transform_info_imp(transform_display *dp, png_structp pp, png_infop pi) /* Don't need sBIT here, but it must be set to non-zero to avoid * arithmetic overflows. */ - test_pixel.have_tRNS = dp->this.is_transparent; + test_pixel.have_tRNS = dp->this.is_transparent != 0; test_pixel.red_sBIT = test_pixel.green_sBIT = test_pixel.blue_sBIT = test_pixel.alpha_sBIT = test_pixel.sample_depth; @@ -6015,13 +6114,14 @@ transform_image_validate(transform_display *dp, png_const_structp pp, unsigned int r, g, b, a; /* Find out what we think the pixel should be: */ - image_pixel_init(&in_pixel, std, in_ct, in_bd, x, dp->this.palette); + image_pixel_init(&in_pixel, std, in_ct, in_bd, x, dp->this.palette, + NULL); in_pixel.red_sBIT = red_sBIT; in_pixel.green_sBIT = green_sBIT; in_pixel.blue_sBIT = blue_sBIT; in_pixel.alpha_sBIT = alpha_sBIT; - in_pixel.have_tRNS = have_tRNS; + in_pixel.have_tRNS = have_tRNS != 0; /* For error detection, below. */ r = in_pixel.red; @@ -6029,12 +6129,18 @@ transform_image_validate(transform_display *dp, png_const_structp pp, b = in_pixel.blue; a = in_pixel.alpha; + /* This applies the transforms to the input date, including output + * format operations which must be used when reading the output + * pixel that libpng produces. + */ dp->transform_list->mod(dp->transform_list, &in_pixel, pp, dp); /* Read the output pixel and compare it to what we got, we don't - * use the error field here, so no need to update sBIT. + * use the error field here, so no need to update sBIT. in_pixel + * says whether we expect libpng to change the output format. */ - image_pixel_init(&out_pixel, pRow, out_ct, out_bd, x, out_palette); + image_pixel_init(&out_pixel, pRow, out_ct, out_bd, x, out_palette, + &in_pixel); /* We don't expect changes to the index here even if the bit depth is * changed. @@ -6815,14 +6921,14 @@ image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this, * conversion adds another +/-2 in the 16-bit case and * +/-(1<<(15-PNG_MAX_GAMMA_8)) in the 8-bit case. */ - that->pm->limit += -# if PNG_MAX_GAMMA_8 < 14 - pow((that->this.bit_depth == 16 ? - 8. : 6. + (1<<(15-PNG_MAX_GAMMA_8)))/65535, data.gamma); -# else - pow((that->this.bit_depth == 16 ? - 8. : 8. + (1<<(15-PNG_MAX_GAMMA_8)))/65535, data.gamma); -# endif + that->pm->limit += pow( +# if PNG_MAX_GAMMA_8 < 14 + (that->this.bit_depth == 16 ? 8. : + 6. + (1<<(15-PNG_MAX_GAMMA_8))) +# else + 8. +# endif + /65535, data.gamma); } else @@ -6834,18 +6940,18 @@ image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this, * When DIGITIZE is set because a pre-1.7 version of libpng is being * tested allow a bigger slack. * - * NOTE: this magic number was determined by experiment to be 1.1 (when - * using fixed point arithmetic). There's no great merit to the value - * below, however it only affects the limit used for checking for - * internal calculation errors, not the actual limit imposed by - * pngvalid on the output errors. + * NOTE: this magic number was determined by experiment to be 1.25. + * There's no great merit to the value below, however it only affects + * the limit used for checking for internal calculation errors, not + * the actual limit imposed by pngvalid on the output errors. */ - that->pm->limit += + that->pm->limit += pow( # if DIGITIZE - pow(1.1 /255, data.gamma); + 1.25 # else - pow(1.0 /255, data.gamma); + 1.0 # endif + /255, data.gamma); } } @@ -7328,7 +7434,7 @@ image_transform_png_set_background_set(PNG_CONST image_transform *this, } image_pixel_init(&data, random_bytes, colour_type, - bit_depth, 0/*x*/, 0/*unused: palette*/); + bit_depth, 0/*x*/, 0/*unused: palette*/, NULL/*format*/); /* Extract the background colour from this image_pixel, but make sure the * unused fields of 'back' are garbage. @@ -7434,22 +7540,329 @@ IT(background); * right answer. */ /* png_set_invert_alpha */ -/*NOTE: TBD NYI */ +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED +/* Invert the alpha channel + * + * png_set_invert_alpha(png_structrp png_ptr) + */ +static void +image_transform_png_set_invert_alpha_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + png_set_invert_alpha(pp); + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_invert_alpha_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->colour_type & 4) + that->alpha_inverted = 1; + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_invert_alpha_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(bit_depth) + + this->next = *that; + *that = this; + + /* Only has an effect on pixels with alpha: */ + return (colour_type & 4) != 0; +} + +IT(invert_alpha); +#undef PT +#define PT ITSTRUCT(invert_alpha) + +#endif /* PNG_READ_INVERT_ALPHA_SUPPORTED */ /* png_set_bgr */ -/*NOTE: TBD NYI */ +#ifdef PNG_READ_BGR_SUPPORTED +/* Swap R,G,B channels to order B,G,R. + * + * png_set_bgr(png_structrp png_ptr) + * + * This only has an effect on RGB and RGBA pixels. + */ +static void +image_transform_png_set_bgr_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + png_set_bgr(pp); + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_bgr_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->colour_type == PNG_COLOR_TYPE_RGB || + that->colour_type == PNG_COLOR_TYPE_RGBA) + that->swap_rgb = 1; + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_bgr_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(bit_depth) + + this->next = *that; + *that = this; + + return colour_type == PNG_COLOR_TYPE_RGB || + colour_type == PNG_COLOR_TYPE_RGBA; +} + +IT(bgr); +#undef PT +#define PT ITSTRUCT(bgr) + +#endif /* PNG_READ_BGR_SUPPORTED */ /* png_set_swap_alpha */ -/*NOTE: TBD NYI */ +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED +/* Put the alpha channel first. + * + * png_set_swap_alpha(png_structrp png_ptr) + * + * This only has an effect on GA and RGBA pixels. + */ +static void +image_transform_png_set_swap_alpha_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + png_set_swap_alpha(pp); + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_swap_alpha_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->colour_type == PNG_COLOR_TYPE_GA || + that->colour_type == PNG_COLOR_TYPE_RGBA) + that->alpha_first = 1; + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_swap_alpha_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(bit_depth) + + this->next = *that; + *that = this; + + return colour_type == PNG_COLOR_TYPE_GA || + colour_type == PNG_COLOR_TYPE_RGBA; +} + +IT(swap_alpha); +#undef PT +#define PT ITSTRUCT(swap_alpha) + +#endif /* PNG_READ_SWAP_ALPHA_SUPPORTED */ /* png_set_swap */ -/*NOTE: TBD NYI */ +#ifdef PNG_READ_SWAP_SUPPORTED +/* Byte swap 16-bit components. + * + * png_set_swap(png_structrp png_ptr) + */ +static void +image_transform_png_set_swap_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + png_set_swap(pp); + this->next->set(this->next, that, pp, pi); +} -/* png_set_filler, (png_structp png_ptr, png_uint_32 filler, int flags)); */ -/*NOTE: TBD NYI */ +static void +image_transform_png_set_swap_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->bit_depth == 16) + that->swap16 = 1; + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_swap_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(colour_type) + + this->next = *that; + *that = this; + + return bit_depth == 16; +} + +IT(swap); +#undef PT +#define PT ITSTRUCT(swap) + +#endif /* PNG_READ_SWAP_SUPPORTED */ + +#ifdef PNG_READ_FILLER_SUPPORTED +/* Add a filler byte to 8-bit Gray or 24-bit RGB images. + * + * png_set_filler, (png_structp png_ptr, png_uint_32 filler, int flags)); + * + * Flags: + * + * PNG_FILLER_BEFORE + * PNG_FILLER_AFTER + */ +#define data ITDATA(filler) +static struct +{ + png_uint_32 filler; + int flags; +} data; + +static void +image_transform_png_set_filler_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + /* Need a random choice for 'before' and 'after' as well as for the + * filler. The 'filler' value has all 32 bits set, but only bit_depth + * will be used. At this point we don't know bit_depth. + */ + RANDOMIZE(data.filler); + data.flags = random_choice(); + + png_set_filler(pp, data.filler, data.flags); + + /* The standard display handling stuff also needs to know that + * there is a filler, so set that here. + */ + that->this.filler = 1; + + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_filler_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->bit_depth >= 8 && + (that->colour_type == PNG_COLOR_TYPE_RGB || + that->colour_type == PNG_COLOR_TYPE_GRAY)) + { + PNG_CONST unsigned int max = (1U << that->bit_depth)-1; + that->alpha = data.filler & max; + that->alphaf = ((double)that->alpha) / max; + that->alphae = 0; + + /* The filler has been stored in the alpha channel, we must record + * that this has been done for the checking later on, the color + * type is faked to have an alpha channel, but libpng won't report + * this; the app has to know the extra channel is there and this + * was recording in standard_display::filler above. + */ + that->colour_type |= 4; /* alpha added */ + that->alpha_first = data.flags == PNG_FILLER_BEFORE; + } + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_filler_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + this->next = *that; + *that = this; + + return bit_depth >= 8 && (colour_type == PNG_COLOR_TYPE_RGB || + colour_type == PNG_COLOR_TYPE_GRAY); +} + +#undef data +IT(filler); +#undef PT +#define PT ITSTRUCT(filler) /* png_set_add_alpha, (png_structp png_ptr, png_uint_32 filler, int flags)); */ -/*NOTE: TBD NYI */ +/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ +#define data ITDATA(add_alpha) +static struct +{ + png_uint_32 filler; + int flags; +} data; + +static void +image_transform_png_set_add_alpha_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + /* Need a random choice for 'before' and 'after' as well as for the + * filler. The 'filler' value has all 32 bits set, but only bit_depth + * will be used. At this point we don't know bit_depth. + */ + RANDOMIZE(data.filler); + data.flags = random_choice(); + + png_set_add_alpha(pp, data.filler, data.flags); + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_add_alpha_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->bit_depth >= 8 && + (that->colour_type == PNG_COLOR_TYPE_RGB || + that->colour_type == PNG_COLOR_TYPE_GRAY)) + { + PNG_CONST unsigned int max = (1U << that->bit_depth)-1; + that->alpha = data.filler & max; + that->alphaf = ((double)that->alpha) / max; + that->alphae = 0; + + that->colour_type |= 4; /* alpha added */ + that->alpha_first = data.flags == PNG_FILLER_BEFORE; + } + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_add_alpha_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + this->next = *that; + *that = this; + + return bit_depth >= 8 && (colour_type == PNG_COLOR_TYPE_RGB || + colour_type == PNG_COLOR_TYPE_GRAY); +} + +#undef data +IT(add_alpha); +#undef PT +#define PT ITSTRUCT(add_alpha) + +#endif /* PNG_READ_FILLER_SUPPORTED */ /* png_set_packing */ #ifdef PNG_READ_PACK_SUPPORTED @@ -7504,13 +7917,174 @@ IT(packing); #endif /* PNG_READ_PACK_SUPPORTED */ /* png_set_packswap */ -/*NOTE: TBD NYI */ +#ifdef PNG_READ_PACKSWAP_SUPPORTED +/* Swap pixels packed into bytes; reverses the order on screen so that + * the high order bits correspond to the rightmost pixels. + * + * png_set_packswap(png_structrp png_ptr) + */ +static void +image_transform_png_set_packswap_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + png_set_packswap(pp); + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_packswap_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->bit_depth < 8) + that->littleendian = 1; + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_packswap_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(colour_type) + + this->next = *that; + *that = this; + + return bit_depth < 8; +} + +IT(packswap); +#undef PT +#define PT ITSTRUCT(packswap) + +#endif /* PNG_READ_PACKSWAP_SUPPORTED */ + /* png_set_invert_mono */ -/*NOTE: TBD NYI */ +#ifdef PNG_READ_INVERT_MONO_SUPPORTED +/* Invert the gray channel + * + * png_set_invert_mono(png_structrp png_ptr) + */ +static void +image_transform_png_set_invert_mono_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + png_set_invert_mono(pp); + this->next->set(this->next, that, pp, pi); +} -/* png_set_shift(png_structp, png_const_color_8p true_bits) */ -/*NOTE: TBD NYI */ +static void +image_transform_png_set_invert_mono_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + if (that->colour_type & 4) + that->mono_inverted = 1; + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_invert_mono_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(bit_depth) + + this->next = *that; + *that = this; + + /* Only has an effect on pixels with no colour: */ + return (colour_type & 2) == 0; +} + +IT(invert_mono); +#undef PT +#define PT ITSTRUCT(invert_mono) + +#endif /* PNG_READ_INVERT_MONO_SUPPORTED */ + +#ifdef PNG_READ_SHIFT_SUPPORTED +/* png_set_shift(png_structp, png_const_color_8p true_bits) + * + * The output pixels will be shifted by the given true_bits + * values. + */ +#define data ITDATA(shift) +static png_color_8 data; + +static void +image_transform_png_set_shift_set(PNG_CONST image_transform *this, + transform_display *that, png_structp pp, png_infop pi) +{ + /* Get a random set of shifts. The shifts need to do something + * to test the transform, so they are limited to the bit depth + * of the input image. Notice that in the following the 'gray' + * field is randomized independently. This acts as a check that + * libpng does use the correct field. + */ + PNG_CONST unsigned int depth = that->this.bit_depth; + + data.red = (png_byte)/*SAFE*/(random_mod(depth)+1); + data.green = (png_byte)/*SAFE*/(random_mod(depth)+1); + data.blue = (png_byte)/*SAFE*/(random_mod(depth)+1); + data.gray = (png_byte)/*SAFE*/(random_mod(depth)+1); + data.alpha = (png_byte)/*SAFE*/(random_mod(depth)+1); + + png_set_shift(pp, &data); + this->next->set(this->next, that, pp, pi); +} + +static void +image_transform_png_set_shift_mod(PNG_CONST image_transform *this, + image_pixel *that, png_const_structp pp, + PNG_CONST transform_display *display) +{ + /* Copy the correct values into the sBIT fields, libpng does not do + * anything to palette data: + */ + if (that->colour_type != PNG_COLOR_TYPE_PALETTE) + { + that->sig_bits = 1; + + /* The sBIT fields are reset to the values previously sent to + * png_set_shift according to the colour type. + * does. + */ + if (that->colour_type & 2) /* RGB channels */ + { + that->red_sBIT = data.red; + that->green_sBIT = data.green; + that->blue_sBIT = data.blue; + } + + else /* One grey channel */ + that->red_sBIT = that->green_sBIT = that->blue_sBIT = data.gray; + + that->alpha_sBIT = data.alpha; + } + + this->next->mod(this->next, that, pp, display); +} + +static int +image_transform_png_set_shift_add(image_transform *this, + PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth) +{ + UNUSED(bit_depth) + + this->next = *that; + *that = this; + + return colour_type != PNG_COLOR_TYPE_PALETTE; +} + +IT(shift); +#undef PT +#define PT ITSTRUCT(shift) + +#endif /* PNG_READ_SHIFT_SUPPORTED */ #ifdef THIS_IS_THE_PROFORMA static void @@ -8822,9 +9396,9 @@ gamma_image_validate(gamma_display *dp, png_const_structp pp, /* Record the palette index for index images. */ PNG_CONST unsigned int in_index = - in_ct == 3 ? sample(std, 3, in_bd, x, 0) : 256; + in_ct == 3 ? sample(std, 3, in_bd, x, 0, 0, 0) : 256; PNG_CONST unsigned int out_index = - out_ct == 3 ? sample(std, 3, out_bd, x, 0) : 256; + out_ct == 3 ? sample(std, 3, out_bd, x, 0, 0, 0) : 256; /* Handle input alpha - png_set_background will cause the output * alpha to disappear so there is nothing to check. @@ -8834,7 +9408,7 @@ gamma_image_validate(gamma_display *dp, png_const_structp pp, { PNG_CONST unsigned int input_alpha = in_ct == 3 ? dp->this.palette[in_index].alpha : - sample(std, in_ct, in_bd, x, samples_per_pixel); + sample(std, in_ct, in_bd, x, samples_per_pixel, 0, 0); unsigned int output_alpha = 65536 /* as a flag value */; @@ -8846,7 +9420,7 @@ gamma_image_validate(gamma_display *dp, png_const_structp pp, else if ((out_ct & PNG_COLOR_MASK_ALPHA) != 0) output_alpha = sample(pRow, out_ct, out_bd, x, - samples_per_pixel); + samples_per_pixel, 0, 0); if (output_alpha != 65536) alpha = gamma_component_validate("alpha", &vi, input_alpha, @@ -8865,30 +9439,30 @@ gamma_image_validate(gamma_display *dp, png_const_structp pp, /* Handle grayscale or RGB components. */ if ((in_ct & PNG_COLOR_MASK_COLOR) == 0) /* grayscale */ (void)gamma_component_validate("gray", &vi, - sample(std, in_ct, in_bd, x, 0), - sample(pRow, out_ct, out_bd, x, 0), alpha/*component*/, - vi.background_red); + sample(std, in_ct, in_bd, x, 0, 0, 0), + sample(pRow, out_ct, out_bd, x, 0, 0, 0), + alpha/*component*/, vi.background_red); else /* RGB or palette */ { (void)gamma_component_validate("red", &vi, in_ct == 3 ? in_palette[in_index].red : - sample(std, in_ct, in_bd, x, 0), + sample(std, in_ct, in_bd, x, 0, 0, 0), out_ct == 3 ? out_palette[out_index].red : - sample(pRow, out_ct, out_bd, x, 0), + sample(pRow, out_ct, out_bd, x, 0, 0, 0), alpha/*component*/, vi.background_red); (void)gamma_component_validate("green", &vi, in_ct == 3 ? in_palette[in_index].green : - sample(std, in_ct, in_bd, x, 1), + sample(std, in_ct, in_bd, x, 1, 0, 0), out_ct == 3 ? out_palette[out_index].green : - sample(pRow, out_ct, out_bd, x, 1), + sample(pRow, out_ct, out_bd, x, 1, 0, 0), alpha/*component*/, vi.background_green); (void)gamma_component_validate("blue", &vi, in_ct == 3 ? in_palette[in_index].blue : - sample(std, in_ct, in_bd, x, 2), + sample(std, in_ct, in_bd, x, 2, 0, 0), out_ct == 3 ? out_palette[out_index].blue : - sample(pRow, out_ct, out_bd, x, 2), + sample(pRow, out_ct, out_bd, x, 2, 0, 0), alpha/*component*/, vi.background_blue); } }