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| Rev | Author | Line No. | Line |
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| 4680 | right-hear | 1 | #include "fitz.h" |
| 2 | |||
| 3 | #include |
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| 4 | #include |
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| 5 | |||
| 6 | typedef struct fz_dctd_s fz_dctd; |
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| 7 | |||
| 8 | struct fz_dctd_s |
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| 9 | { |
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| 10 | fz_stream *chain; |
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| 11 | int color_transform; |
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| 12 | int init; |
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| 13 | int stride; |
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| 14 | unsigned char *scanline; |
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| 15 | unsigned char *rp, *wp; |
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| 16 | struct jpeg_decompress_struct cinfo; |
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| 17 | struct jpeg_source_mgr srcmgr; |
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| 18 | struct jpeg_error_mgr errmgr; |
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| 19 | jmp_buf jb; |
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| 20 | char msg[JMSG_LENGTH_MAX]; |
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| 21 | }; |
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| 22 | |||
| 23 | static void error_exit(j_common_ptr cinfo) |
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| 24 | { |
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| 25 | fz_dctd *state = cinfo->client_data; |
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| 26 | cinfo->err->format_message(cinfo, state->msg); |
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| 27 | longjmp(state->jb, 1); |
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| 28 | } |
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| 29 | |||
| 30 | static void init_source(j_decompress_ptr cinfo) |
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| 31 | { |
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| 32 | /* nothing to do */ |
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| 33 | } |
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| 34 | |||
| 35 | static void term_source(j_decompress_ptr cinfo) |
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| 36 | { |
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| 37 | /* nothing to do */ |
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| 38 | } |
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| 39 | |||
| 40 | static boolean fill_input_buffer(j_decompress_ptr cinfo) |
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| 41 | { |
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| 42 | struct jpeg_source_mgr *src = cinfo->src; |
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| 43 | fz_dctd *state = cinfo->client_data; |
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| 44 | fz_stream *chain = state->chain; |
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| 45 | |||
| 46 | chain->rp = chain->wp; |
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| 47 | fz_fill_buffer(chain); |
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| 48 | src->next_input_byte = chain->rp; |
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| 49 | src->bytes_in_buffer = chain->wp - chain->rp; |
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| 50 | |||
| 51 | if (src->bytes_in_buffer == 0) |
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| 52 | { |
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| 53 | static unsigned char eoi[2] = { 0xFF, JPEG_EOI }; |
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| 54 | fz_warn("premature end of file in jpeg"); |
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| 55 | src->next_input_byte = eoi; |
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| 56 | src->bytes_in_buffer = 2; |
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| 57 | } |
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| 58 | |||
| 59 | return 1; |
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| 60 | } |
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| 61 | |||
| 62 | static void skip_input_data(j_decompress_ptr cinfo, long num_bytes) |
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| 63 | { |
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| 64 | struct jpeg_source_mgr *src = cinfo->src; |
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| 65 | if (num_bytes > 0) |
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| 66 | { |
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| 67 | while ((size_t)num_bytes > src->bytes_in_buffer) |
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| 68 | { |
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| 69 | num_bytes -= src->bytes_in_buffer; |
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| 70 | (void) src->fill_input_buffer(cinfo); |
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| 71 | } |
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| 72 | src->next_input_byte += num_bytes; |
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| 73 | src->bytes_in_buffer -= num_bytes; |
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| 74 | } |
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| 75 | } |
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| 76 | |||
| 77 | static int |
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| 78 | read_dctd(fz_stream *stm, unsigned char *buf, int len) |
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| 79 | { |
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| 80 | fz_dctd *state = stm->state; |
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| 81 | j_decompress_ptr cinfo = &state->cinfo; |
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| 82 | unsigned char *p = buf; |
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| 83 | unsigned char *ep = buf + len; |
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| 84 | |||
| 85 | if (setjmp(state->jb)) |
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| 86 | { |
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| 87 | if (cinfo->src) |
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| 88 | state->chain->rp = state->chain->wp - cinfo->src->bytes_in_buffer; |
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| 89 | return fz_throw("jpeg error: %s", state->msg); |
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| 90 | } |
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| 91 | |||
| 92 | if (!state->init) |
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| 93 | { |
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| 94 | cinfo->client_data = state; |
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| 95 | cinfo->err = &state->errmgr; |
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| 96 | jpeg_std_error(cinfo->err); |
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| 97 | cinfo->err->error_exit = error_exit; |
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| 98 | jpeg_create_decompress(cinfo); |
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| 99 | |||
| 100 | cinfo->src = &state->srcmgr; |
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| 101 | cinfo->src->init_source = init_source; |
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| 102 | cinfo->src->fill_input_buffer = fill_input_buffer; |
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| 103 | cinfo->src->skip_input_data = skip_input_data; |
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| 104 | cinfo->src->resync_to_restart = jpeg_resync_to_restart; |
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| 105 | cinfo->src->term_source = term_source; |
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| 106 | cinfo->src->next_input_byte = state->chain->rp; |
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| 107 | cinfo->src->bytes_in_buffer = state->chain->wp - state->chain->rp; |
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| 108 | |||
| 109 | jpeg_read_header(cinfo, 1); |
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| 110 | |||
| 111 | /* speed up jpeg decoding a bit */ |
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| 112 | cinfo->dct_method = JDCT_FASTEST; |
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| 113 | cinfo->do_fancy_upsampling = FALSE; |
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| 114 | |||
| 115 | /* default value if ColorTransform is not set */ |
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| 116 | if (state->color_transform == -1) |
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| 117 | { |
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| 118 | if (state->cinfo.num_components == 3) |
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| 119 | state->color_transform = 1; |
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| 120 | else |
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| 121 | state->color_transform = 0; |
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| 122 | } |
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| 123 | |||
| 124 | if (cinfo->saw_Adobe_marker) |
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| 125 | state->color_transform = cinfo->Adobe_transform; |
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| 126 | |||
| 127 | /* Guess the input colorspace, and set output colorspace accordingly */ |
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| 128 | switch (cinfo->num_components) |
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| 129 | { |
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| 130 | case 3: |
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| 131 | if (state->color_transform) |
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| 132 | cinfo->jpeg_color_space = JCS_YCbCr; |
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| 133 | else |
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| 134 | cinfo->jpeg_color_space = JCS_RGB; |
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| 135 | break; |
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| 136 | case 4: |
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| 137 | if (state->color_transform) |
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| 138 | cinfo->jpeg_color_space = JCS_YCCK; |
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| 139 | else |
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| 140 | cinfo->jpeg_color_space = JCS_CMYK; |
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| 141 | break; |
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| 142 | } |
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| 143 | |||
| 144 | jpeg_start_decompress(cinfo); |
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| 145 | |||
| 146 | state->stride = cinfo->output_width * cinfo->output_components; |
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| 147 | state->scanline = fz_malloc(state->stride); |
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| 148 | state->rp = state->scanline; |
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| 149 | state->wp = state->scanline; |
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| 150 | |||
| 151 | state->init = 1; |
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| 152 | } |
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| 153 | |||
| 154 | while (state->rp < state->wp && p < ep) |
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| 155 | *p++ = *state->rp++; |
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| 156 | |||
| 157 | while (p < ep) |
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| 158 | { |
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| 159 | if (cinfo->output_scanline == cinfo->output_height) |
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| 160 | break; |
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| 161 | |||
| 162 | if (p + state->stride <= ep) |
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| 163 | { |
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| 164 | jpeg_read_scanlines(cinfo, &p, 1); |
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| 165 | p += state->stride; |
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| 166 | } |
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| 167 | else |
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| 168 | { |
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| 169 | jpeg_read_scanlines(cinfo, &state->scanline, 1); |
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| 170 | state->rp = state->scanline; |
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| 171 | state->wp = state->scanline + state->stride; |
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| 172 | } |
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| 173 | |||
| 174 | while (state->rp < state->wp && p < ep) |
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| 175 | *p++ = *state->rp++; |
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| 176 | } |
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| 177 | |||
| 178 | return p - buf; |
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| 179 | } |
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| 180 | |||
| 181 | static void |
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| 182 | close_dctd(fz_stream *stm) |
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| 183 | { |
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| 184 | fz_dctd *state = stm->state; |
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| 185 | |||
| 186 | if (setjmp(state->jb)) |
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| 187 | { |
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| 188 | state->chain->rp = state->chain->wp - state->cinfo.src->bytes_in_buffer; |
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| 189 | fz_warn("jpeg error: %s", state->msg); |
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| 190 | goto skip; |
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| 191 | } |
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| 192 | |||
| 193 | if (state->init) |
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| 194 | jpeg_finish_decompress(&state->cinfo); |
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| 195 | |||
| 196 | skip: |
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| 197 | state->chain->rp = state->chain->wp - state->cinfo.src->bytes_in_buffer; |
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| 198 | jpeg_destroy_decompress(&state->cinfo); |
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| 199 | fz_free(state->scanline); |
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| 200 | fz_close(state->chain); |
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| 201 | fz_free(state); |
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| 202 | } |
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| 203 | |||
| 204 | fz_stream * |
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| 205 | fz_open_dctd(fz_stream *chain, fz_obj *params) |
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| 206 | { |
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| 207 | fz_dctd *state; |
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| 208 | fz_obj *obj; |
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| 209 | |||
| 210 | state = fz_malloc(sizeof(fz_dctd)); |
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| 211 | memset(state, 0, sizeof(fz_dctd)); |
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| 212 | state->chain = chain; |
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| 213 | state->color_transform = -1; /* unset */ |
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| 214 | state->init = 0; |
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| 215 | |||
| 216 | obj = fz_dict_gets(params, "ColorTransform"); |
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| 217 | if (obj) |
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| 218 | state->color_transform = fz_to_int(obj); |
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| 219 | |||
| 220 | return fz_new_stream(state, read_dctd, close_dctd); |
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| 221 | } |