ref: a5f7064637d1d9efe7c0a0920d81f70f99c6d456
dir: /jbig2_generic.c/
/* jbig2dec Copyright (c) 2002 artofcode LLC. This program 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 2 of the License, or (at your option) any later version. $Id: jbig2_generic.c,v 1.9 2002/06/24 15:51:57 giles Exp $ */ /** * Generic region handlers. **/ #include <stdint.h> #include <stddef.h> #ifdef OUTPUT_PBM #include <stdio.h> #endif #include "jbig2.h" #include "jbig2_priv.h" #include "jbig2_arith.h" #include "jbig2_generic.h" #include "jbig2_mmr.h" static int jbig2_decode_generic_template0(Jbig2Ctx *ctx, Jbig2Segment *segment, const Jbig2GenericRegionParams *params, Jbig2ArithState *as, Jbig2Image *image, Jbig2ArithCx *GB_stats) { const int GBW = image->width; const int GBH = image->height; const int rowstride = image->stride; int x, y; byte *gbreg_line = (byte *)image->data; bool LTP = 0; /* todo: currently we only handle the nominal gbat location */ #ifdef OUTPUT_PBM printf("P4\n%d %d\n", GBW, GBH); #endif for (y = 0; y < GBH; y++) { uint32_t CONTEXT; uint32_t line_m1; uint32_t line_m2; int padded_width = (GBW + 7) & -8; line_m1 = (y >= 1) ? gbreg_line[-rowstride] : 0; line_m2 = (y >= 2) ? gbreg_line[-(rowstride << 1)] << 6 : 0; CONTEXT = (line_m1 & 0x7f0) | (line_m2 & 0xf800); /* 6.2.5.7 3d */ for (x = 0; x < padded_width; x += 8) { byte result = 0; int x_minor; int minor_width = GBW - x > 8 ? 8 : GBW - x; if (y >= 1) line_m1 = (line_m1 << 8) | (x + 8 < GBW ? gbreg_line[-rowstride + (x >> 3) + 1] : 0); if (y >= 2) line_m2 = (line_m2 << 8) | (x + 8 < GBW ? gbreg_line[-(rowstride << 1) + (x >> 3) + 1] << 6: 0); /* This is the speed-critical inner loop. */ for (x_minor = 0; x_minor < minor_width; x_minor++) { bool bit; bit = jbig2_arith_decode(as, &GB_stats[CONTEXT]); result |= bit << (7 - x_minor); CONTEXT = ((CONTEXT & 0x7bf7) << 1) | bit | ((line_m1 >> (7 - x_minor)) & 0x10) | ((line_m2 >> (7 - x_minor)) & 0x800); } gbreg_line[x >> 3] = result; } #ifdef OUTPUT_PBM fwrite(gbreg_line, 1, rowstride, stdout); #endif gbreg_line += rowstride; } return 0; } static int jbig2_decode_generic_template1(Jbig2Ctx *ctx, Jbig2Segment *segment, const Jbig2GenericRegionParams *params, Jbig2ArithState *as, Jbig2Image *image, Jbig2ArithCx *GB_stats) { const int GBW = image->width; const int GBH = image->height; const int rowstride = image->stride; int x, y; byte *gbreg_line = (byte *)image->data; bool LTP = 0; /* todo: currently we only handle the nominal gbat location */ #ifdef OUTPUT_PBM printf("P4\n%d %d\n", GBW, GBH); #endif for (y = 0; y < GBH; y++) { uint32_t CONTEXT; uint32_t line_m1; uint32_t line_m2; int padded_width = (GBW + 7) & -8; line_m1 = (y >= 1) ? gbreg_line[-rowstride] : 0; line_m2 = (y >= 2) ? gbreg_line[-(rowstride << 1)] << 5 : 0; CONTEXT = ((line_m1 >> 1) & 0x1f8) | ((line_m2 >> 1) & 0x1e00); /* 6.2.5.7 3d */ for (x = 0; x < padded_width; x += 8) { byte result = 0; int x_minor; int minor_width = GBW - x > 8 ? 8 : GBW - x; if (y >= 1) line_m1 = (line_m1 << 8) | (x + 8 < GBW ? gbreg_line[-rowstride + (x >> 3) + 1] : 0); if (y >= 2) line_m2 = (line_m2 << 8) | (x + 8 < GBW ? gbreg_line[-(rowstride << 1) + (x >> 3) + 1] << 5: 0); /* This is the speed-critical inner loop. */ for (x_minor = 0; x_minor < minor_width; x_minor++) { bool bit; bit = jbig2_arith_decode(as, &GB_stats[CONTEXT]); result |= bit << (7 - x_minor); CONTEXT = ((CONTEXT & 0xefb) << 1) | bit | ((line_m1 >> (8 - x_minor)) & 0x8) | ((line_m2 >> (8 - x_minor)) & 0x200); } gbreg_line[x >> 3] = result; } #ifdef OUTPUT_PBM fwrite(gbreg_line, 1, rowstride, stdout); #endif gbreg_line += rowstride; } return 0; } static int jbig2_decode_generic_template2(Jbig2Ctx *ctx, Jbig2Segment *segment, const Jbig2GenericRegionParams *params, Jbig2ArithState *as, Jbig2Image *image, Jbig2ArithCx *GB_stats) { const int GBW = image->width; const int GBH = image->height; const int rowstride = image->stride; int x, y; byte *gbreg_line = (byte *)image->data; bool LTP = 0; /* todo: currently we only handle the nominal gbat location */ #ifdef OUTPUT_PBM printf("P4\n%d %d\n", GBW, GBH); #endif for (y = 0; y < GBH; y++) { uint32_t CONTEXT; uint32_t line_m1; uint32_t line_m2; int padded_width = (GBW + 7) & -8; line_m1 = (y >= 1) ? gbreg_line[-rowstride] : 0; line_m2 = (y >= 2) ? gbreg_line[-(rowstride << 1)] << 4 : 0; CONTEXT = ((line_m1 >> 3) & 0x7c) | ((line_m2 >> 3) & 0x380); /* 6.2.5.7 3d */ for (x = 0; x < padded_width; x += 8) { byte result = 0; int x_minor; int minor_width = GBW - x > 8 ? 8 : GBW - x; if (y >= 1) line_m1 = (line_m1 << 8) | (x + 8 < GBW ? gbreg_line[-rowstride + (x >> 3) + 1] : 0); if (y >= 2) line_m2 = (line_m2 << 8) | (x + 8 < GBW ? gbreg_line[-(rowstride << 1) + (x >> 3) + 1] << 4: 0); /* This is the speed-critical inner loop. */ for (x_minor = 0; x_minor < minor_width; x_minor++) { bool bit; bit = jbig2_arith_decode(as, &GB_stats[CONTEXT]); result |= bit << (7 - x_minor); CONTEXT = ((CONTEXT & 0x1bd) << 1) | bit | ((line_m1 >> (10 - x_minor)) & 0x4) | ((line_m2 >> (10 - x_minor)) & 0x80); } gbreg_line[x >> 3] = result; } #ifdef OUTPUT_PBM fwrite(gbreg_line, 1, rowstride, stdout); #endif gbreg_line += rowstride; } return 0; } static int jbig2_decode_generic_template2a(Jbig2Ctx *ctx, Jbig2Segment *segment, const Jbig2GenericRegionParams *params, Jbig2ArithState *as, Jbig2Image *image, Jbig2ArithCx *GB_stats) { const int GBW = image->width; const int GBH = image->height; const int rowstride = image->stride; int x, y; byte *gbreg_line = (byte *)image->data; bool LTP = 0; /* This is a special case for GBATX1 = 3, GBATY1 = -1 */ #ifdef OUTPUT_PBM printf("P4\n%d %d\n", GBW, GBH); #endif for (y = 0; y < GBH; y++) { uint32_t CONTEXT; uint32_t line_m1; uint32_t line_m2; int padded_width = (GBW + 7) & -8; line_m1 = (y >= 1) ? gbreg_line[-rowstride] : 0; line_m2 = (y >= 2) ? gbreg_line[-(rowstride << 1)] << 4 : 0; CONTEXT = ((line_m1 >> 3) & 0x78) | ((line_m1 >> 2) & 0x4) | ((line_m2 >> 3) & 0x380); /* 6.2.5.7 3d */ for (x = 0; x < padded_width; x += 8) { byte result = 0; int x_minor; int minor_width = GBW - x > 8 ? 8 : GBW - x; if (y >= 1) line_m1 = (line_m1 << 8) | (x + 8 < GBW ? gbreg_line[-rowstride + (x >> 3) + 1] : 0); if (y >= 2) line_m2 = (line_m2 << 8) | (x + 8 < GBW ? gbreg_line[-(rowstride << 1) + (x >> 3) + 1] << 4: 0); /* This is the speed-critical inner loop. */ for (x_minor = 0; x_minor < minor_width; x_minor++) { bool bit; bit = jbig2_arith_decode(as, &GB_stats[CONTEXT]); result |= bit << (7 - x_minor); CONTEXT = ((CONTEXT & 0x1b9) << 1) | bit | ((line_m1 >> (10 - x_minor)) & 0x8) | ((line_m1 >> (9 - x_minor)) & 0x4) | ((line_m2 >> (10 - x_minor)) & 0x80); } gbreg_line[x >> 3] = result; } #ifdef OUTPUT_PBM fwrite(gbreg_line, 1, rowstride, stdout); #endif gbreg_line += rowstride; } return 0; } /** * jbig2_decode_generic_region: Decode a generic region. * @ctx: The context for allocation and error reporting. * @params: Parameters, as specified in Table 2. * @as: Arithmetic decoder state. * @gbreg: Where to store the decoded data. * @GB_stats: Arithmetic stats. * * Decodes a generic region, according to section 6.2. The caller should * have allocated the memory for @gbreg, which is packed 8 pixels to a * byte, scanlines aligned to one byte boundaries. * * Because this API is based on an arithmetic decoding state, it is * not suitable for MMR decoding. * * Return code: 0 on success. **/ int jbig2_decode_generic_region(Jbig2Ctx *ctx, Jbig2Segment *segment, const Jbig2GenericRegionParams *params, Jbig2ArithState *as, Jbig2Image *image, Jbig2ArithCx *GB_stats) { if (!params->MMR && params->GBTEMPLATE == 0) return jbig2_decode_generic_template0(ctx, segment, params, as, image, GB_stats); else if (!params->MMR && params->GBTEMPLATE == 1) return jbig2_decode_generic_template1(ctx, segment, params, as, image, GB_stats); else if (!params->MMR && params->GBTEMPLATE == 2) { if (params->gbat[0] == 3 && params->gbat[1] == 255) return jbig2_decode_generic_template2a(ctx, segment, params, as, image, GB_stats); else return jbig2_decode_generic_template2(ctx, segment, params, as, image, GB_stats); } { int i; for (i = 0; i < 8; i++) printf ("gbat[%d] = %d\n", i, params->gbat[i]); } jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number, "decode_generic_region: MMR=%d, GBTEMPLATE=%d NYI", params->MMR, params->GBTEMPLATE); return -1; } int jbig2_immediate_generic_region(Jbig2Ctx *ctx, Jbig2Segment *segment, const uint8_t *segment_data) { Jbig2RegionSegmentInfo rsi; byte seg_flags; int8_t gbat[8]; int offset; int gbat_bytes = 0; Jbig2GenericRegionParams params; int code; Jbig2Image *image; Jbig2WordStream *ws; Jbig2ArithState *as; Jbig2ArithCx *GB_stats = NULL; /* 7.4.6 */ if (segment->data_length < 18) return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number, "Segment too short"); jbig2_get_region_segment_info(&rsi, segment_data); jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number, "generic region: %d x %d @ (%d, %d), flags = %02x", rsi.width, rsi.height, rsi.x, rsi.y, rsi.flags); /* 7.4.6.2 */ seg_flags = segment_data[17]; jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number, "segment flags = %02x", seg_flags); if ((seg_flags & 1) && (seg_flags & 6)) jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number, "MMR is 1, but GBTEMPLATE is not 0"); /* 7.4.6.3 */ if (!(seg_flags & 1)) { gbat_bytes = (seg_flags & 6) ? 2 : 8; if (18 + gbat_bytes > segment->data_length) return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number, "Segment too short"); memcpy(gbat, segment_data + 18, gbat_bytes); jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number, "gbat: %d, %d", gbat[0], gbat[1]); } offset = 18 + gbat_bytes; /* Table 34 */ params.MMR = seg_flags & 1; params.GBTEMPLATE = (seg_flags & 6) >> 1; params.TPGDON = (seg_flags & 8) >> 3; params.USESKIP = 0; memcpy (params.gbat, gbat, gbat_bytes); image = jbig2_image_new(ctx, rsi.width, rsi.height); jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number, "allocated %d x %d image buffer for region decode results", rsi.width, rsi.height); if (params.MMR) { code = jbig2_decode_generic_mmr(ctx, segment, ¶ms, segment_data + offset, segment->data_length - offset, image); } else { int stats_size = params.GBTEMPLATE == 0 ? 65536 : params.GBTEMPLATE == 1 ? 8192 : 1024; GB_stats = jbig2_alloc(ctx->allocator, stats_size); memset(GB_stats, 0, stats_size); ws = jbig2_word_stream_buf_new(ctx, segment_data + offset, segment->data_length - offset); as = jbig2_arith_new(ctx, ws); code = jbig2_decode_generic_region(ctx, segment, ¶ms, as, image, GB_stats); } /* todo: free ws, as */ jbig2_image_compose(ctx, ctx->pages[ctx->current_page].image, image, rsi.x, rsi.y, JBIG2_COMPOSE_OR); jbig2_image_free(ctx, image); jbig2_free(ctx->allocator, GB_stats); return code; }