On Jan 10, 2008 4:33 AM, Vesa Jääskeläinen <[EMAIL PROTECTED]> wrote: > Nice job for implementing JPEG. This is the major reason I made the > bitmap loader interface, to allow other people to write loaders... now > if we would just have PNG support ;)
This is my next project. > I know lots of JPEG loaders seems to use longjmp for error handling, > personally I don't like it, but I suppose it is ok. In grub2 you could > just check if grub_errno != GRUB_ERR_NONE and then just return and at > that level do the same check. This mechanism works a bit like c++'s > exceptions. error can occur deep within function call. i can check for return value, but longjmp seems easier. > > + get_word (data); > > not important word? The first word of a segment is the length, but we don't need it. > try to keep malloc on own line and then check for pointer or for > grub_errno (or both). ok. > +static int > +get_huff_leng (struct grub_jpeg_data *data, int num) _length? change to get_huff_code. > > + get_word (data); > > + id = get_byte (data); > > + if (id >= 0x10) > > 0x10? the upper 4-bit is precision, 0 is 8-bit, 1 is 16-bit, etc. > > +static void > > +decode_du (struct grub_jpeg_data *data, int id, int *du) > > +{ > > + int pos, h1, h2, qt; > > + > > + grub_memset (du, 0, sizeof (int) * 64); > > du is always that size ? perhaps add warning about it to prototype, or > provide length? now i use type jpeg_data_unit. > > + if (get_marker (data) != 0xD8) > > 0xD8? use symbols now. diff --git a/conf/i386-pc.rmk b/conf/i386-pc.rmk index a46bc74..4beeeff 100644 --- a/conf/i386-pc.rmk +++ b/conf/i386-pc.rmk @@ -136,7 +136,7 @@ pkglib_MODULES = biosdisk.mod _chain.mod _linux.mod linux.mod normal.mod \ _multiboot.mod chain.mod multiboot.mod reboot.mod halt.mod \ vbe.mod vbetest.mod vbeinfo.mod video.mod gfxterm.mod \ videotest.mod play.mod bitmap.mod tga.mod cpuid.mod serial.mod \ - ata.mod vga.mod + ata.mod vga.mod jpeg.mod # For biosdisk.mod. biosdisk_mod_SOURCES = disk/i386/pc/biosdisk.c @@ -249,6 +249,11 @@ tga_mod_SOURCES = video/readers/tga.c tga_mod_CFLAGS = $(COMMON_CFLAGS) tga_mod_LDFLAGS = $(COMMON_LDFLAGS) +# For jpeg.mod +jpeg_mod_SOURCES = video/readers/jpeg.c +jpeg_mod_CFLAGS = $(COMMON_CFLAGS) +jpeg_mod_LDFLAGS = $(COMMON_LDFLAGS) + # For cpuid.mod. cpuid_mod_SOURCES = commands/i386/cpuid.c cpuid_mod_CFLAGS = $(COMMON_CFLAGS) diff --git a/video/readers/jpeg.c b/video/readers/jpeg.c new file mode 100755 index 0000000..bb1eda5 --- /dev/null +++ b/video/readers/jpeg.c @@ -0,0 +1,839 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2008 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <grub/bitmap.h> +#include <grub/types.h> +#include <grub/normal.h> +#include <grub/dl.h> +#include <grub/mm.h> +#include <grub/misc.h> +#include <grub/arg.h> +#include <grub/file.h> +#include <grub/setjmp.h> + +/* Uncomment following define to enable JPEG debug. */ +//#define JPEG_DEBUG + +typedef enum +{ /* JPEG marker codes */ + M_SOF0 = 0xc0, + M_SOF1 = 0xc1, + M_SOF2 = 0xc2, + M_SOF3 = 0xc3, + + M_SOF5 = 0xc5, + M_SOF6 = 0xc6, + M_SOF7 = 0xc7, + + M_JPG = 0xc8, + M_SOF9 = 0xc9, + M_SOF10 = 0xca, + M_SOF11 = 0xcb, + + M_SOF13 = 0xcd, + M_SOF14 = 0xce, + M_SOF15 = 0xcf, + + M_DHT = 0xc4, + + M_DAC = 0xcc, + + M_RST0 = 0xd0, + M_RST1 = 0xd1, + M_RST2 = 0xd2, + M_RST3 = 0xd3, + M_RST4 = 0xd4, + M_RST5 = 0xd5, + M_RST6 = 0xd6, + M_RST7 = 0xd7, + + M_SOI = 0xd8, + M_EOI = 0xd9, + M_SOS = 0xda, + M_DQT = 0xdb, + M_DNL = 0xdc, + M_DRI = 0xdd, + M_DHP = 0xde, + M_EXP = 0xdf, + + M_APP0 = 0xe0, + M_APP1 = 0xe1, + M_APP2 = 0xe2, + M_APP3 = 0xe3, + M_APP4 = 0xe4, + M_APP5 = 0xe5, + M_APP6 = 0xe6, + M_APP7 = 0xe7, + M_APP8 = 0xe8, + M_APP9 = 0xe9, + M_APP10 = 0xea, + M_APP11 = 0xeb, + M_APP12 = 0xec, + M_APP13 = 0xed, + M_APP14 = 0xee, + M_APP15 = 0xef, + + M_JPG0 = 0xf0, + M_JPG13 = 0xfd, + M_COM = 0xfe, + + M_TEM = 0x01, + + M_ERROR = 0x100 +} JPEG_MARKER; + +typedef int jpeg_data_unit[64]; + +struct grub_jpeg_data +{ + grub_file_t file; + grub_jmp_buf jumper; + + int image_width; + int image_height; + + grub_uint8_t *huff_value[4]; + int huff_offset[4][16]; + int huff_maxval[4][16]; + + grub_uint8_t quan_table[2][64]; + int comp_index[3][3]; + + jpeg_data_unit ydu[4]; + jpeg_data_unit crdu; + jpeg_data_unit cbdu; + + int Cr_r_tab[256], Cb_b_tab[256], Cr_g_tab[256], Cb_g_tab[256]; + + int dc_value[3]; + + int bit_mask, bit_save; + + struct grub_video_bitmap **bitmap; +}; + + +static grub_uint8_t +get_byte (struct grub_jpeg_data *data) +{ + grub_uint8_t r; + + if (grub_file_read (data->file, (char *) &r, 1) != 1) + grub_longjmp (data->jumper, 1); + + return r; +} + +static grub_uint16_t +get_word (struct grub_jpeg_data *data) +{ + grub_uint16_t aa, bb; + + aa = get_byte (data); + bb = get_byte (data); + return (aa << 8) + bb; +} + +static int +get_bit (struct grub_jpeg_data *data) +{ + int ret; + + if (data->bit_mask == 0) + { + data->bit_save = get_byte (data); + if (data->bit_save == 0xFF) + { + if (get_byte (data) != 0) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, + "jpeg: invalid 0xFF in data stream"); + grub_longjmp (data->jumper, 1); + } + } + data->bit_mask = 0x80; + } + + ret = (data->bit_save & data->bit_mask); + data->bit_mask >>= 1; + return ret; +} + +static int +get_huff_code (struct grub_jpeg_data *data, int num) +{ + int value, i, bit; + + if (num == 0) + return 0; + + bit = get_bit (data); + value = (bit != 0); + for (i = 1; i < num; i++) + value = value * 2 + (get_bit (data) != 0); + if (!bit) + value += 1 - (1 << num); + + return value; +} + +static int +get_huff_base (struct grub_jpeg_data *data, int id) +{ + int code, i; + + code = 0; + for (i = 0; i < 16; i++) + { + code <<= 1; + if (get_bit (data)) + code++; + if (code < data->huff_maxval[id][i]) + return data->huff_value[id][code + data->huff_offset[id][i]]; + } + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: huffman decode fails"); + grub_longjmp (data->jumper, 1); + return 0; +} + +static void +decode_huff_table (struct grub_jpeg_data *data) +{ + int id, ac, i, n, base, ofs; + grub_uint8_t count[16]; + + get_word (data); + id = get_byte (data); + ac = (id >> 4); + id &= 0xF; + if (id > 1) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: too many huffman table"); + grub_longjmp (data->jumper, 1); + } + + if (grub_file_read (data->file, (char *) &count, sizeof (count)) != + sizeof (count)) + grub_longjmp (data->jumper, 1); + + n = 0; + for (i = 0; i < 16; i++) + n += count[i]; + + id += ac * 2; + data->huff_value[id] = grub_malloc (n); + if (data->huff_value[id] == NULL) + grub_longjmp (data->jumper, 1); + + if (grub_file_read (data->file, (char *) data->huff_value[id], n) != n) + grub_longjmp (data->jumper, 1); + + base = 0; + ofs = 0; + for (i = 0; i < 16; i++) + { + base += count[i]; + ofs += count[i]; + + data->huff_maxval[id][i] = base; + data->huff_offset[id][i] = ofs - base; + + base <<= 1; + } +} + +static void +decode_quan_table (struct grub_jpeg_data *data) +{ + int id; + + get_word (data); + id = get_byte (data); + if (id >= 0x10) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, + "jpeg: only 8-bit precision is supported"); + grub_longjmp (data->jumper, 1); + } + + if (id > 1) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, + "jpeg: too many quantization table"); + grub_longjmp (data->jumper, 1); + } + + if (grub_file_read (data->file, (char *) &data->quan_table[id], 64) != 64) + grub_longjmp (data->jumper, 1); +} + +static void +decode_sof (struct grub_jpeg_data *data) +{ + int nc, i; + + get_word (data); + if (get_byte (data) != 8) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, + "jpeg: only 8-bit precision is supported"); + grub_longjmp (data->jumper, 1); + } + + data->image_height = get_word (data); + data->image_width = get_word (data); + + if ((!data->image_height) || (!data->image_width)) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid image size"); + grub_longjmp (data->jumper, 1); + } + + nc = get_byte (data); + if (nc != 3) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: component count must be 3"); + grub_longjmp (data->jumper, 1); + } + + for (i = 0; i < nc; i++) + { + int id, ss; + + id = get_byte (data) - 1; + if ((id < 0) || (id >= 3)) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid index"); + grub_longjmp (data->jumper, 1); + } + ss = get_byte (data); + if (((!id) && (ss != 0x22)) || ((id) && (ss != 0x11))) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, + "jpeg: only support 2:1:1 sampling"); + grub_longjmp (data->jumper, 1); + } + data->comp_index[id][0] = get_byte (data); + } +} + +#define DCTSIZE 8 + +#define CONST_BITS 8 +#define PASS1_BITS 2 + +#define FIX_1_082392200 ((int) 277) /* FIX(1.082392200) */ +#define FIX_1_414213562 ((int) 362) /* FIX(1.414213562) */ +#define FIX_1_847759065 ((int) 473) /* FIX(1.847759065) */ +#define FIX_2_613125930 ((int) 669) /* FIX(2.613125930) */ + +#define ONE ((long) 1) +#define DESCALE(x,n) (((x) + (ONE << ((n)-1))) >> (n)) + +#define MULTIPLY(var,const) DESCALE((var) * (const), CONST_BITS) + +static const grub_uint8_t natural_order[64] = { + 0, 1, 8, 16, 9, 2, 3, 10, + 17, 24, 32, 25, 18, 11, 4, 5, + 12, 19, 26, 33, 40, 48, 41, 34, + 27, 20, 13, 6, 7, 14, 21, 28, + 35, 42, 49, 56, 57, 50, 43, 36, + 29, 22, 15, 23, 30, 37, 44, 51, + 58, 59, 52, 45, 38, 31, 39, 46, + 53, 60, 61, 54, 47, 55, 62, 63 +}; + +static const int aanscales[64] = { + /* precomputed values scaled up by 14 bits */ + 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520, + 22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270, + 21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906, + 19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315, + 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520, + 12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552, + 8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446, + 4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247 +}; + +static void +idct_transform (jpeg_data_unit du) +{ + int *pd; + int ctr; + int tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; + int tmp10, tmp11, tmp12, tmp13; + int z5, z10, z11, z12, z13; + + /* Pass 1: process columns from input, store into work array. */ + + pd = du; + for (ctr = DCTSIZE; ctr > 0; ctr--) + { + if ((pd[DCTSIZE * 1] | pd[DCTSIZE * 2] | pd[DCTSIZE * 3] | + pd[DCTSIZE * 4] | pd[DCTSIZE * 5] | pd[DCTSIZE * 6] | + pd[DCTSIZE * 7]) == 0) + { + pd[DCTSIZE * 1] = pd[DCTSIZE * 2] + = pd[DCTSIZE * 3] = pd[DCTSIZE * 4] + = pd[DCTSIZE * 5] = pd[DCTSIZE * 6] + = pd[DCTSIZE * 7] = pd[DCTSIZE * 0]; + + pd++; /* advance pointers to next column */ + continue; + } + + /* Even part */ + + tmp0 = pd[DCTSIZE * 0]; + tmp1 = pd[DCTSIZE * 2]; + tmp2 = pd[DCTSIZE * 4]; + tmp3 = pd[DCTSIZE * 6]; + + tmp10 = tmp0 + tmp2; /* phase 3 */ + tmp11 = tmp0 - tmp2; + + tmp13 = tmp1 + tmp3; /* phases 5-3 */ + tmp12 = MULTIPLY (tmp1 - tmp3, FIX_1_414213562) - tmp13; /* 2*c4 */ + + tmp0 = tmp10 + tmp13; /* phase 2 */ + tmp3 = tmp10 - tmp13; + tmp1 = tmp11 + tmp12; + tmp2 = tmp11 - tmp12; + + /* Odd part */ + + tmp4 = pd[DCTSIZE * 1]; + tmp5 = pd[DCTSIZE * 3]; + tmp6 = pd[DCTSIZE * 5]; + tmp7 = pd[DCTSIZE * 7]; + + z13 = tmp6 + tmp5; /* phase 6 */ + z10 = tmp6 - tmp5; + z11 = tmp4 + tmp7; + z12 = tmp4 - tmp7; + + tmp7 = z11 + z13; /* phase 5 */ + tmp11 = MULTIPLY (z11 - z13, FIX_1_414213562); /* 2*c4 */ + + z5 = MULTIPLY (z10 + z12, FIX_1_847759065); /* 2*c2 */ + tmp10 = MULTIPLY (z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */ + tmp12 = MULTIPLY (z10, -FIX_2_613125930) + z5; /* -2*(c2+c6) */ + + + tmp6 = tmp12 - tmp7; /* phase 2 */ + tmp5 = tmp11 - tmp6; + tmp4 = tmp10 + tmp5; + + pd[DCTSIZE * 0] = (int) (tmp0 + tmp7); + pd[DCTSIZE * 7] = (int) (tmp0 - tmp7); + pd[DCTSIZE * 1] = (int) (tmp1 + tmp6); + pd[DCTSIZE * 6] = (int) (tmp1 - tmp6); + pd[DCTSIZE * 2] = (int) (tmp2 + tmp5); + pd[DCTSIZE * 5] = (int) (tmp2 - tmp5); + pd[DCTSIZE * 4] = (int) (tmp3 + tmp4); + pd[DCTSIZE * 3] = (int) (tmp3 - tmp4); + + pd++; /* advance pointers to next column */ + } + + /* Pass 2: process rows from work array, store into output array. */ + /* Note that we must descale the results by a factor of 8 == 2**3, */ + /* and also undo the PASS1_BITS scaling. */ + + pd = du; + for (ctr = 0; ctr < DCTSIZE; ctr++) + { + /* Even part */ + + tmp10 = pd[0] + pd[4]; + tmp11 = pd[0] - pd[4]; + + tmp13 = pd[2] + pd[6]; + tmp12 = MULTIPLY (pd[2] - pd[6], FIX_1_414213562) - tmp13; + + tmp0 = tmp10 + tmp13; + tmp3 = tmp10 - tmp13; + tmp1 = tmp11 + tmp12; + tmp2 = tmp11 - tmp12; + + /* Odd part */ + + z13 = pd[5] + pd[3]; + z10 = pd[5] - pd[3]; + z11 = pd[1] + pd[7]; + z12 = pd[1] - pd[7]; + + tmp7 = z11 + z13; /* phase 5 */ + tmp11 = MULTIPLY (z11 - z13, FIX_1_414213562); /* 2*c4 */ + + z5 = MULTIPLY (z10 + z12, FIX_1_847759065); /* 2*c2 */ + tmp10 = MULTIPLY (z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */ + tmp12 = MULTIPLY (z10, -FIX_2_613125930) + z5; /* -2*(c2+c6) */ + + tmp6 = tmp12 - tmp7; /* phase 2 */ + tmp5 = tmp11 - tmp6; + tmp4 = tmp10 + tmp5; + + /* Final output stage: scale down by a factor of 8 and range-limit */ + + pd[0] = DESCALE (tmp0 + tmp7, PASS1_BITS + 3) + 128; + pd[7] = DESCALE (tmp0 - tmp7, PASS1_BITS + 3) + 128; + pd[1] = DESCALE (tmp1 + tmp6, PASS1_BITS + 3) + 128; + pd[6] = DESCALE (tmp1 - tmp6, PASS1_BITS + 3) + 128; + pd[2] = DESCALE (tmp2 + tmp5, PASS1_BITS + 3) + 128; + pd[5] = DESCALE (tmp2 - tmp5, PASS1_BITS + 3) + 128; + pd[4] = DESCALE (tmp3 + tmp4, PASS1_BITS + 3) + 128; + pd[3] = DESCALE (tmp3 - tmp4, PASS1_BITS + 3) + 128; + + pd += DCTSIZE; /* advance pointer to next row */ + } + + for (ctr = 0; ctr < 64; ctr++) + { + if (du[ctr] < 0) + du[ctr] = 0; + if (du[ctr] > 255) + du[ctr] = 255; + } +} + +static void +decode_du (struct grub_jpeg_data *data, int id, jpeg_data_unit du) +{ + int pos, h1, h2, qt; + + grub_memset (du, 0, sizeof (jpeg_data_unit)); + + qt = data->comp_index[id][0]; + h1 = data->comp_index[id][1]; + h2 = data->comp_index[id][2]; + + data->dc_value[id] += get_huff_code (data, get_huff_base (data, h1)); + + du[0] = + data->dc_value[id] * DESCALE ((int) data->quan_table[qt][0] * + (int) aanscales[0], 14 - 2); + pos = 1; + while (pos < 64) + { + int num, val; + + num = get_huff_base (data, h2); + if (!num) + break; + val = get_huff_code (data, num & 0xF); + num >>= 4; + pos += num; + du[natural_order[pos]] = + val * DESCALE ((int) data->quan_table[qt][pos] * + (int) aanscales[natural_order[pos]], 14 - 2); + pos++; + } + + idct_transform (du); +} + +#define SCALEBITS 16 /* speediest right-shift on some machines */ +#define ONE_HALF ((int) 1 << (SCALEBITS-1)) +#define FIX(x) ((int) ((x) * (1L<<SCALEBITS) + 0.5)) + +static void +build_color_table (struct grub_jpeg_data *data) +{ + int i, x; + + for (i = 0, x = -128; i <= 255; i++, x++) + { + data->Cr_r_tab[i] = (int) (FIX (1.40200) * x + ONE_HALF) >> SCALEBITS; + data->Cb_b_tab[i] = (int) (FIX (1.77200) * x + ONE_HALF) >> SCALEBITS; + data->Cr_g_tab[i] = (-FIX (0.71414)) * x; + data->Cb_g_tab[i] = (-FIX (0.34414)) * x + ONE_HALF; + } +} + +static void +decode_sos (struct grub_jpeg_data *data) +{ + int nc, i, r1, c1; + grub_uint8_t *ptr; + + get_word (data); + nc = get_byte (data); + + if (nc != 3) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: component count must be 3"); + grub_longjmp (data->jumper, 1); + } + + for (i = 0; i < nc; i++) + { + int id, ht; + + id = get_byte (data) - 1; + if ((id < 0) || (id >= 3)) + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid index"); + grub_longjmp (data->jumper, 1); + } + + ht = get_byte (data); + data->comp_index[id][1] = (ht >> 4); + data->comp_index[id][2] = (ht & 0xF) + 2; + } + + get_byte (data); + get_word (data); + + if (grub_video_bitmap_create (data->bitmap, data->image_width, + data->image_height, + GRUB_VIDEO_BLIT_FORMAT_R8G8B8)) + grub_longjmp (data->jumper, 1); + + ptr = (*data->bitmap)->data; + data->bit_mask = 0x0; + + for (r1 = 0; r1 < (data->image_height >> 4); r1++) + for (c1 = 0; c1 < (data->image_width >> 4); c1++) + { + int r2, c2, r3, c3; + + decode_du (data, 0, data->ydu[0]); + decode_du (data, 0, data->ydu[1]); + + decode_du (data, 0, data->ydu[2]); + decode_du (data, 0, data->ydu[3]); + + decode_du (data, 1, data->cbdu); + decode_du (data, 2, data->crdu); + + for (r2 = 0; r2 < 2; r2++) + for (c2 = 0; c2 < 2; c2++) + for (r3 = 0; r3 < 8; r3++) + for (c3 = 0; c3 < 8; c3++) + { + int i0, i1, i2, cr, cb, dd; + + i0 = + ((r1 * 16 + r2 * 8 + r3) * (data->image_width) + c1 * 16 + + c2 * 8 + c3) * 3; + i1 = r3 * 8 + c3; + i2 = (r2 * 32 + c2 * 4) + (r3 >> 1) * 8 + (c3 >> 1); + + cr = data->crdu[i2]; + cb = data->cbdu[i2]; + + if (((c3 & 1) != 0) && ((i2 & 7) != 7)) + { + cr = (cr + data->crdu[i2 + 1]) >> 1; + cb = (cb + data->cbdu[i2 + 1]) >> 1; + } + + if (((r3 & 1) != 0) && (i2 < 64 - 8)) + { + cr = (cr + data->crdu[i2 + 8]) >> 1; + cb = (cb + data->cbdu[i2 + 8]) >> 1; + } + + /* Red */ + dd = data->ydu[r2 * 2 + c2][i1] + data->Cr_r_tab[cr]; + if (dd < 0) + dd = 0; + if (dd > 255) + dd = 255; + ptr[i0] = dd; + + /* Green */ + dd = + data->ydu[r2 * 2 + c2][i1] + + ((data->Cb_g_tab[cb] + data->Cr_g_tab[cr]) >> SCALEBITS); + if (dd < 0) + dd = 0; + if (dd > 255) + dd = 255; + ptr[i0 + 1] = dd; + + /* Blue */ + dd = data->ydu[r2 * 2 + c2][i1] + data->Cb_b_tab[cb]; + if (dd < 0) + dd = 0; + if (dd > 255) + dd = 255; + ptr[i0 + 2] = dd; + } + } +} + + +static grub_uint8_t +get_marker (struct grub_jpeg_data *data) +{ + grub_uint8_t r; + + r = get_byte (data); + + if (r != 0xFF) /* escape character */ + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid maker"); + grub_longjmp (data->jumper, 1); + } + + return get_byte (data); +} + +static void +decode_jpeg (struct grub_jpeg_data *data) +{ + build_color_table (data); + + if (get_marker (data) != M_SOI) /* Start Of Image */ + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: invalid jpeg file"); + grub_longjmp (data->jumper, 1); + } + + while (1) + { + grub_uint8_t marker; + + marker = get_marker (data); +#ifdef JPEG_DEBUG + grub_printf ("jpeg marker: %x\n", marker); +#endif + switch (marker) + { + case M_DHT: /* Define Huffman Table */ + decode_huff_table (data); + break; + case M_DQT: /* Define Quantization Table */ + decode_quan_table (data); + break; + case M_SOF0: /* Start Of Frame 0 */ + decode_sof (data); + break; + case M_SOS: /* Start Of Scan */ + decode_sos (data); + break; + case M_EOI: /* End Of Image */ + return; + case M_APP0: /* JFIF APP0 segment */ + case M_COM: /* Comment */ + { + grub_uint16_t sz; + + sz = get_word (data); + grub_file_seek (data->file, data->file->offset + sz - 2); + break; + } + default: + grub_error (GRUB_ERR_BAD_FILE_TYPE, "jpeg: unrecognized marker %x", + marker); + grub_longjmp (data->jumper, 1); + } + } +} + +static grub_err_t +grub_video_reader_jpeg (struct grub_video_bitmap **bitmap, + const char *filename) +{ + grub_file_t file; + struct grub_jpeg_data *data; + + file = grub_file_open (filename); + if (!file) + return grub_errno; + + data = grub_malloc (sizeof (*data)); + if (data != NULL) + { + int i; + + grub_memset (data, 0, sizeof (*data)); + data->file = file; + data->bitmap = bitmap; + if (!grub_setjmp (data->jumper)) + decode_jpeg (data); + + for (i = 0; i < 4; i++) + if (data->huff_value[i]) + grub_free (data->huff_value[i]); + grub_free (data); + } + + if (grub_errno != GRUB_ERR_NONE) + { + grub_video_bitmap_destroy (*bitmap); + *bitmap = 0; + } + + grub_file_close (file); + return grub_errno; +} + +#if defined(JPEG_DEBUG) +static grub_err_t +grub_cmd_jpegtest (struct grub_arg_list *state __attribute__ ((unused)), + int argc, char **args) +{ + struct grub_video_bitmap *bitmap = 0; + + if (argc != 1) + return grub_error (GRUB_ERR_BAD_ARGUMENT, "file name required"); + + grub_video_reader_jpeg (&bitmap, args[0]); + if (grub_errno != GRUB_ERR_NONE) + return grub_errno; + + grub_video_bitmap_destroy (bitmap); + + return GRUB_ERR_NONE; +} +#endif + +static struct grub_video_bitmap_reader jpg_reader = { + .extension = ".jpg", + .reader = grub_video_reader_jpeg, + .next = 0 +}; + +static struct grub_video_bitmap_reader jpeg_reader = { + .extension = ".jpeg", + .reader = grub_video_reader_jpeg, + .next = 0 +}; + +GRUB_MOD_INIT (video_reader_jpeg) +{ + grub_video_bitmap_reader_register (&jpg_reader); + grub_video_bitmap_reader_register (&jpeg_reader); +#if defined(JPEG_DEBUG) + grub_register_command ("jpegtest", grub_cmd_jpegtest, + GRUB_COMMAND_FLAG_BOTH, "jpegtest FILE", + "Tests loading of JPEG bitmap.", 0); +#endif +} + +GRUB_MOD_FINI (video_reader_jpeg) +{ +#if defined(JPEG_DEBUG) + grub_unregister_command ("jpegtest"); +#endif + grub_video_bitmap_reader_unregister (&jpeg_reader); + grub_video_bitmap_reader_unregister (&jpg_reader); +} -- Bean _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org http://lists.gnu.org/mailman/listinfo/grub-devel