diff options
Diffstat (limited to '3rdparty/libjpeg/jccolor.c')
-rw-r--r-- | 3rdparty/libjpeg/jccolor.c | 249 |
1 files changed, 197 insertions, 52 deletions
diff --git a/3rdparty/libjpeg/jccolor.c b/3rdparty/libjpeg/jccolor.c index 0a8a4b5d13c..f6b4a493fda 100644 --- a/3rdparty/libjpeg/jccolor.c +++ b/3rdparty/libjpeg/jccolor.c @@ -2,6 +2,7 @@ * jccolor.c * * Copyright (C) 1991-1996, Thomas G. Lane. + * Modified 2011-2013 by Guido Vollbeding. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * @@ -28,13 +29,25 @@ typedef my_color_converter * my_cconvert_ptr; /**************** RGB -> YCbCr conversion: most common case **************/ /* - * YCbCr is defined per CCIR 601-1, except that Cb and Cr are - * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. - * The conversion equations to be implemented are therefore - * Y = 0.29900 * R + 0.58700 * G + 0.11400 * B - * Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B + CENTERJSAMPLE - * Cr = 0.50000 * R - 0.41869 * G - 0.08131 * B + CENTERJSAMPLE - * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.) + * YCbCr is defined per Recommendation ITU-R BT.601-7 (03/2011), + * previously known as Recommendation CCIR 601-1, except that Cb and Cr + * are normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. + * sRGB (standard RGB color space) is defined per IEC 61966-2-1:1999. + * sYCC (standard luma-chroma-chroma color space with extended gamut) + * is defined per IEC 61966-2-1:1999 Amendment A1:2003 Annex F. + * bg-sRGB and bg-sYCC (big gamut standard color spaces) + * are defined per IEC 61966-2-1:1999 Amendment A1:2003 Annex G. + * Note that the derived conversion coefficients given in some of these + * documents are imprecise. The general conversion equations are + * Y = Kr * R + (1 - Kr - Kb) * G + Kb * B + * Cb = 0.5 * (B - Y) / (1 - Kb) + * Cr = 0.5 * (R - Y) / (1 - Kr) + * With Kr = 0.299 and Kb = 0.114 (derived according to SMPTE RP 177-1993 + * from the 1953 FCC NTSC primaries and CIE Illuminant C), + * the conversion equations to be implemented are therefore + * Y = 0.299 * R + 0.587 * G + 0.114 * B + * Cb = -0.168735892 * R - 0.331264108 * G + 0.5 * B + CENTERJSAMPLE + * Cr = 0.5 * R - 0.418687589 * G - 0.081312411 * B + CENTERJSAMPLE * Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2, * rather than CENTERJSAMPLE, for Cb and Cr. This gave equal positive and * negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0) @@ -48,9 +61,9 @@ typedef my_color_converter * my_cconvert_ptr; * For even more speed, we avoid doing any multiplications in the inner loop * by precalculating the constants times R,G,B for all possible values. * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table); - * for 12-bit samples it is still acceptable. It's not very reasonable for - * 16-bit samples, but if you want lossless storage you shouldn't be changing - * colorspace anyway. + * for 9-bit to 12-bit samples it is still acceptable. It's not very + * reasonable for 16-bit samples, but if you want lossless storage you + * shouldn't be changing colorspace anyway. * The CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included * in the tables to save adding them separately in the inner loop. */ @@ -95,21 +108,21 @@ rgb_ycc_start (j_compress_ptr cinfo) (TABLE_SIZE * SIZEOF(INT32))); for (i = 0; i <= MAXJSAMPLE; i++) { - rgb_ycc_tab[i+R_Y_OFF] = FIX(0.29900) * i; - rgb_ycc_tab[i+G_Y_OFF] = FIX(0.58700) * i; - rgb_ycc_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF; - rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.16874)) * i; - rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.33126)) * i; + rgb_ycc_tab[i+R_Y_OFF] = FIX(0.299) * i; + rgb_ycc_tab[i+G_Y_OFF] = FIX(0.587) * i; + rgb_ycc_tab[i+B_Y_OFF] = FIX(0.114) * i + ONE_HALF; + rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.168735892)) * i; + rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.331264108)) * i; /* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr. * This ensures that the maximum output will round to MAXJSAMPLE * not MAXJSAMPLE+1, and thus that we don't have to range-limit. */ - rgb_ycc_tab[i+B_CB_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1; + rgb_ycc_tab[i+B_CB_OFF] = FIX(0.5) * i + CBCR_OFFSET + ONE_HALF-1; /* B=>Cb and R=>Cr tables are the same - rgb_ycc_tab[i+R_CR_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1; + rgb_ycc_tab[i+R_CR_OFF] = FIX(0.5) * i + CBCR_OFFSET + ONE_HALF-1; */ - rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.41869)) * i; - rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.08131)) * i; + rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.418687589)) * i; + rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.081312411)) * i; } } @@ -132,8 +145,8 @@ rgb_ycc_convert (j_compress_ptr cinfo, JDIMENSION output_row, int num_rows) { my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; - register int r, g, b; register INT32 * ctab = cconvert->rgb_ycc_tab; + register int r, g, b; register JSAMPROW inptr; register JSAMPROW outptr0, outptr1, outptr2; register JDIMENSION col; @@ -149,7 +162,6 @@ rgb_ycc_convert (j_compress_ptr cinfo, r = GETJSAMPLE(inptr[RGB_RED]); g = GETJSAMPLE(inptr[RGB_GREEN]); b = GETJSAMPLE(inptr[RGB_BLUE]); - inptr += RGB_PIXELSIZE; /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations * must be too; we do not need an explicit range-limiting operation. * Hence the value being shifted is never negative, and we don't @@ -167,6 +179,7 @@ rgb_ycc_convert (j_compress_ptr cinfo, outptr2[col] = (JSAMPLE) ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) >> SCALEBITS); + inptr += RGB_PIXELSIZE; } } } @@ -188,8 +201,8 @@ rgb_gray_convert (j_compress_ptr cinfo, JDIMENSION output_row, int num_rows) { my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; - register int r, g, b; register INT32 * ctab = cconvert->rgb_ycc_tab; + register int r, g, b; register JSAMPROW inptr; register JSAMPROW outptr; register JDIMENSION col; @@ -197,17 +210,16 @@ rgb_gray_convert (j_compress_ptr cinfo, while (--num_rows >= 0) { inptr = *input_buf++; - outptr = output_buf[0][output_row]; - output_row++; + outptr = output_buf[0][output_row++]; for (col = 0; col < num_cols; col++) { r = GETJSAMPLE(inptr[RGB_RED]); g = GETJSAMPLE(inptr[RGB_GREEN]); b = GETJSAMPLE(inptr[RGB_BLUE]); - inptr += RGB_PIXELSIZE; /* Y */ outptr[col] = (JSAMPLE) ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) >> SCALEBITS); + inptr += RGB_PIXELSIZE; } } } @@ -227,8 +239,8 @@ cmyk_ycck_convert (j_compress_ptr cinfo, JDIMENSION output_row, int num_rows) { my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; - register int r, g, b; register INT32 * ctab = cconvert->rgb_ycc_tab; + register int r, g, b; register JSAMPROW inptr; register JSAMPROW outptr0, outptr1, outptr2, outptr3; register JDIMENSION col; @@ -247,7 +259,6 @@ cmyk_ycck_convert (j_compress_ptr cinfo, b = MAXJSAMPLE - GETJSAMPLE(inptr[2]); /* K passes through as-is */ outptr3[col] = inptr[3]; /* don't need GETJSAMPLE here */ - inptr += 4; /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations * must be too; we do not need an explicit range-limiting operation. * Hence the value being shifted is never negative, and we don't @@ -265,6 +276,49 @@ cmyk_ycck_convert (j_compress_ptr cinfo, outptr2[col] = (JSAMPLE) ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) >> SCALEBITS); + inptr += 4; + } + } +} + + +/* + * Convert some rows of samples to the JPEG colorspace. + * [R,G,B] to [R-G,G,B-G] conversion with modulo calculation + * (forward reversible color transform). + * This can be seen as an adaption of the general RGB->YCbCr + * conversion equation with Kr = Kb = 0, while replacing the + * normalization by modulo calculation. + */ + +METHODDEF(void) +rgb_rgb1_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + register int r, g, b; + register JSAMPROW inptr; + register JSAMPROW outptr0, outptr1, outptr2; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->image_width; + + while (--num_rows >= 0) { + inptr = *input_buf++; + outptr0 = output_buf[0][output_row]; + outptr1 = output_buf[1][output_row]; + outptr2 = output_buf[2][output_row]; + output_row++; + for (col = 0; col < num_cols; col++) { + r = GETJSAMPLE(inptr[RGB_RED]); + g = GETJSAMPLE(inptr[RGB_GREEN]); + b = GETJSAMPLE(inptr[RGB_BLUE]); + /* Assume that MAXJSAMPLE+1 is a power of 2, so that the MOD + * (modulo) operator is equivalent to the bitmask operator AND. + */ + outptr0[col] = (JSAMPLE) ((r - g + CENTERJSAMPLE) & MAXJSAMPLE); + outptr1[col] = (JSAMPLE) g; + outptr2[col] = (JSAMPLE) ((b - g + CENTERJSAMPLE) & MAXJSAMPLE); + inptr += RGB_PIXELSIZE; } } } @@ -273,7 +327,7 @@ cmyk_ycck_convert (j_compress_ptr cinfo, /* * Convert some rows of samples to the JPEG colorspace. * This version handles grayscale output with no conversion. - * The source can be either plain grayscale or YCbCr (since Y == gray). + * The source can be either plain grayscale or YCC (since Y == gray). */ METHODDEF(void) @@ -281,16 +335,15 @@ grayscale_convert (j_compress_ptr cinfo, JSAMPARRAY input_buf, JSAMPIMAGE output_buf, JDIMENSION output_row, int num_rows) { + int instride = cinfo->input_components; register JSAMPROW inptr; register JSAMPROW outptr; register JDIMENSION col; JDIMENSION num_cols = cinfo->image_width; - int instride = cinfo->input_components; while (--num_rows >= 0) { inptr = *input_buf++; - outptr = output_buf[0][output_row]; - output_row++; + outptr = output_buf[0][output_row++]; for (col = 0; col < num_cols; col++) { outptr[col] = inptr[0]; /* don't need GETJSAMPLE() here */ inptr += instride; @@ -301,6 +354,39 @@ grayscale_convert (j_compress_ptr cinfo, /* * Convert some rows of samples to the JPEG colorspace. + * No colorspace conversion, but change from interleaved + * to separate-planes representation. + */ + +METHODDEF(void) +rgb_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + register JSAMPROW inptr; + register JSAMPROW outptr0, outptr1, outptr2; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->image_width; + + while (--num_rows >= 0) { + inptr = *input_buf++; + outptr0 = output_buf[0][output_row]; + outptr1 = output_buf[1][output_row]; + outptr2 = output_buf[2][output_row]; + output_row++; + for (col = 0; col < num_cols; col++) { + /* We can dispense with GETJSAMPLE() here */ + outptr0[col] = inptr[RGB_RED]; + outptr1[col] = inptr[RGB_GREEN]; + outptr2[col] = inptr[RGB_BLUE]; + inptr += RGB_PIXELSIZE; + } + } +} + + +/* + * Convert some rows of samples to the JPEG colorspace. * This version handles multi-component colorspaces without conversion. * We assume input_components == num_components. */ @@ -310,20 +396,20 @@ null_convert (j_compress_ptr cinfo, JSAMPARRAY input_buf, JSAMPIMAGE output_buf, JDIMENSION output_row, int num_rows) { + int ci; + register int nc = cinfo->num_components; register JSAMPROW inptr; register JSAMPROW outptr; register JDIMENSION col; - register int ci; - int nc = cinfo->num_components; JDIMENSION num_cols = cinfo->image_width; while (--num_rows >= 0) { /* It seems fastest to make a separate pass for each component. */ for (ci = 0; ci < nc; ci++) { - inptr = *input_buf; + inptr = input_buf[0] + ci; outptr = output_buf[ci][output_row]; for (col = 0; col < num_cols; col++) { - outptr[col] = inptr[ci]; /* don't need GETJSAMPLE() here */ + *outptr++ = *inptr; /* don't need GETJSAMPLE() here */ inptr += nc; } } @@ -356,7 +442,7 @@ jinit_color_converter (j_compress_ptr cinfo) cconvert = (my_cconvert_ptr) (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(my_color_converter)); - cinfo->cconvert = (struct jpeg_color_converter *) cconvert; + cinfo->cconvert = &cconvert->pub; /* set start_pass to null method until we find out differently */ cconvert->pub.start_pass = null_method; @@ -368,13 +454,13 @@ jinit_color_converter (j_compress_ptr cinfo) break; case JCS_RGB: -#if RGB_PIXELSIZE != 3 + case JCS_BG_RGB: if (cinfo->input_components != RGB_PIXELSIZE) ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); break; -#endif /* else share code with YCbCr */ case JCS_YCbCr: + case JCS_BG_YCC: if (cinfo->input_components != 3) ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); break; @@ -391,41 +477,96 @@ jinit_color_converter (j_compress_ptr cinfo) break; } + /* Support color transform only for RGB colorspaces */ + if (cinfo->color_transform && + cinfo->jpeg_color_space != JCS_RGB && + cinfo->jpeg_color_space != JCS_BG_RGB) + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + /* Check num_components, set conversion method based on requested space */ switch (cinfo->jpeg_color_space) { case JCS_GRAYSCALE: if (cinfo->num_components != 1) ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - if (cinfo->in_color_space == JCS_GRAYSCALE) + switch (cinfo->in_color_space) { + case JCS_GRAYSCALE: + case JCS_YCbCr: + case JCS_BG_YCC: cconvert->pub.color_convert = grayscale_convert; - else if (cinfo->in_color_space == JCS_RGB) { + break; + case JCS_RGB: cconvert->pub.start_pass = rgb_ycc_start; cconvert->pub.color_convert = rgb_gray_convert; - } else if (cinfo->in_color_space == JCS_YCbCr) - cconvert->pub.color_convert = grayscale_convert; - else + break; + default: ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + } break; case JCS_RGB: + case JCS_BG_RGB: if (cinfo->num_components != 3) ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - if (cinfo->in_color_space == JCS_RGB && RGB_PIXELSIZE == 3) - cconvert->pub.color_convert = null_convert; - else + if (cinfo->in_color_space == cinfo->jpeg_color_space) { + switch (cinfo->color_transform) { + case JCT_NONE: + cconvert->pub.color_convert = rgb_convert; + break; + case JCT_SUBTRACT_GREEN: + cconvert->pub.color_convert = rgb_rgb1_convert; + break; + default: + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + } + } else ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); break; case JCS_YCbCr: if (cinfo->num_components != 3) ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - if (cinfo->in_color_space == JCS_RGB) { + switch (cinfo->in_color_space) { + case JCS_RGB: cconvert->pub.start_pass = rgb_ycc_start; cconvert->pub.color_convert = rgb_ycc_convert; - } else if (cinfo->in_color_space == JCS_YCbCr) + break; + case JCS_YCbCr: cconvert->pub.color_convert = null_convert; - else + break; + default: ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + } + break; + + case JCS_BG_YCC: + if (cinfo->num_components != 3) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + switch (cinfo->in_color_space) { + case JCS_RGB: + /* For conversion from normal RGB input to BG_YCC representation, + * the Cb/Cr values are first computed as usual, and then + * quantized further after DCT processing by a factor of + * 2 in reference to the nominal quantization factor. + */ + /* need quantization scale by factor of 2 after DCT */ + cinfo->comp_info[1].component_needed = TRUE; + cinfo->comp_info[2].component_needed = TRUE; + /* compute normal YCC first */ + cconvert->pub.start_pass = rgb_ycc_start; + cconvert->pub.color_convert = rgb_ycc_convert; + break; + case JCS_YCbCr: + /* need quantization scale by factor of 2 after DCT */ + cinfo->comp_info[1].component_needed = TRUE; + cinfo->comp_info[2].component_needed = TRUE; + /*FALLTHROUGH*/ + case JCS_BG_YCC: + /* Pass through for BG_YCC input */ + cconvert->pub.color_convert = null_convert; + break; + default: + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + } break; case JCS_CMYK: @@ -440,13 +581,17 @@ jinit_color_converter (j_compress_ptr cinfo) case JCS_YCCK: if (cinfo->num_components != 4) ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - if (cinfo->in_color_space == JCS_CMYK) { + switch (cinfo->in_color_space) { + case JCS_CMYK: cconvert->pub.start_pass = rgb_ycc_start; cconvert->pub.color_convert = cmyk_ycck_convert; - } else if (cinfo->in_color_space == JCS_YCCK) + break; + case JCS_YCCK: cconvert->pub.color_convert = null_convert; - else + break; + default: ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + } break; default: /* allow null conversion of JCS_UNKNOWN */ |