/* * jdinput.c * * Copyright (C) 1991-1997, Thomas G. Lane. * Modified 2002-2013 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. * * This file contains input control logic for the JPEG decompressor. * These routines are concerned with controlling the decompressor's input * processing (marker reading and coefficient decoding). The actual input * reading is done in jdmarker.c, jdhuff.c, and jdarith.c. */ #define JPEG_INTERNALS#include "jinclude.h"#include "jpeglib.h" /* Private state */ typedef struct { struct jpeg_input_controller pub; /* public fields */ int inheaders; /* Nonzero until first SOS is reached */} my_input_controller; typedef my_input_controller * my_inputctl_ptr; /* Forward declarations */METHODDEF(int) consume_markers JPP((j_decompress_ptr cinfo)); /* * Routines to calculate various quantities related to the size of the image. */ /* * Compute output image dimensions and related values. * NOTE: this is exported for possible use by application. * Hence it mustn't do anything that can't be done twice. */ GLOBAL(void)jpeg_core_output_dimensions (j_decompress_ptr cinfo)/* Do computations that are needed before master selection phase. * This function is used for transcoding and full decompression. */{#ifdef IDCT_SCALING_SUPPORTED int ci; jpeg_component_info *compptr; /* Compute actual output image dimensions and DCT scaling choices. */ if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom) { /* Provide 1/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 1; cinfo->min_DCT_v_scaled_size = 1; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 2) { /* Provide 2/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 2L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 2L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 2; cinfo->min_DCT_v_scaled_size = 2; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 3) { /* Provide 3/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 3L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 3L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 3; cinfo->min_DCT_v_scaled_size = 3; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 4) { /* Provide 4/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 4L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 4L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 4; cinfo->min_DCT_v_scaled_size = 4; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 5) { /* Provide 5/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 5L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 5L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 5; cinfo->min_DCT_v_scaled_size = 5; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 6) { /* Provide 6/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 6L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 6L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 6; cinfo->min_DCT_v_scaled_size = 6; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 7) { /* Provide 7/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 7L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 7L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 7; cinfo->min_DCT_v_scaled_size = 7; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 8) { /* Provide 8/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 8L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 8L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 8; cinfo->min_DCT_v_scaled_size = 8; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 9) { /* Provide 9/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 9L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 9L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 9; cinfo->min_DCT_v_scaled_size = 9; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 10) { /* Provide 10/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 10L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 10L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 10; cinfo->min_DCT_v_scaled_size = 10; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 11) { /* Provide 11/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 11L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 11L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 11; cinfo->min_DCT_v_scaled_size = 11; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 12) { /* Provide 12/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 12L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 12L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 12; cinfo->min_DCT_v_scaled_size = 12; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 13) { /* Provide 13/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 13L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 13L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 13; cinfo->min_DCT_v_scaled_size = 13; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 14) { /* Provide 14/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 14L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 14L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 14; cinfo->min_DCT_v_scaled_size = 14; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 15) { /* Provide 15/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 15L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 15L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 15; cinfo->min_DCT_v_scaled_size = 15; } else { /* Provide 16/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 16L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 16L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 16; cinfo->min_DCT_v_scaled_size = 16; } /* Recompute dimensions of components */ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size; compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size; } #else /* !IDCT_SCALING_SUPPORTED */ /* Hardwire it to "no scaling" */ cinfo->output_width = cinfo->image_width; cinfo->output_height = cinfo->image_height; /* initial_setup has already initialized DCT_scaled_size, * and has computed unscaled downsampled_width and downsampled_height. */ #endif /* IDCT_SCALING_SUPPORTED */} LOCAL(void)initial_setup (j_decompress_ptr cinfo)/* Called once, when first SOS marker is reached */{ int ci; jpeg_component_info *compptr; /* Make sure image isn't bigger than I can handle */ if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION || (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION) ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION); /* Only 8 to 12 bits data precision are supported for DCT based JPEG */ if (cinfo->data_precision < 8 || cinfo->data_precision > 12) ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); /* Check that number of components won't exceed internal array sizes */ if (cinfo->num_components > MAX_COMPONENTS) ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, MAX_COMPONENTS); /* Compute maximum sampling factors; check factor validity */ cinfo->max_h_samp_factor = 1; cinfo->max_v_samp_factor = 1; for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR || compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR) ERREXIT(cinfo, JERR_BAD_SAMPLING); cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor, compptr->h_samp_factor); cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor, compptr->v_samp_factor); } /* Derive block_size, natural_order, and lim_Se */ if (cinfo->is_baseline || (cinfo->progressive_mode && cinfo->comps_in_scan)) { /* no pseudo SOS marker */ cinfo->block_size = DCTSIZE; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; } else switch (cinfo->Se) { case (1*1-1): cinfo->block_size = 1; cinfo->natural_order = jpeg_natural_order; /* not needed */ cinfo->lim_Se = cinfo->Se; break; case (2*2-1): cinfo->block_size = 2; cinfo->natural_order = jpeg_natural_order2; cinfo->lim_Se = cinfo->Se; break; case (3*3-1): cinfo->block_size = 3; cinfo->natural_order = jpeg_natural_order3; cinfo->lim_Se = cinfo->Se; break; case (4*4-1): cinfo->block_size = 4; cinfo->natural_order = jpeg_natural_order4; cinfo->lim_Se = cinfo->Se; break; case (5*5-1): cinfo->block_size = 5; cinfo->natural_order = jpeg_natural_order5; cinfo->lim_Se = cinfo->Se; break; case (6*6-1): cinfo->block_size = 6; cinfo->natural_order = jpeg_natural_order6; cinfo->lim_Se = cinfo->Se; break; case (7*7-1): cinfo->block_size = 7; cinfo->natural_order = jpeg_natural_order7; cinfo->lim_Se = cinfo->Se; break; case (8*8-1): cinfo->block_size = 8; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (9*9-1): cinfo->block_size = 9; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (10*10-1): cinfo->block_size = 10; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (11*11-1): cinfo->block_size = 11; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (12*12-1): cinfo->block_size = 12; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (13*13-1): cinfo->block_size = 13; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (14*14-1): cinfo->block_size = 14; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (15*15-1): cinfo->block_size = 15; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (16*16-1): cinfo->block_size = 16; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; default: ERREXIT4(cinfo, JERR_BAD_PROGRESSION, cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al); break; } /* We initialize DCT_scaled_size and min_DCT_scaled_size to block_size. * In the full decompressor, * this will be overridden by jpeg_calc_output_dimensions in jdmaster.c; * but in the transcoder, * jpeg_calc_output_dimensions is not used, so we must do it here. */ cinfo->min_DCT_h_scaled_size = cinfo->block_size; cinfo->min_DCT_v_scaled_size = cinfo->block_size; /* Compute dimensions of components */ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { compptr->DCT_h_scaled_size = cinfo->block_size; compptr->DCT_v_scaled_size = cinfo->block_size; /* Size in DCT blocks */ compptr->width_in_blocks = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, (long) (cinfo->max_h_samp_factor * cinfo->block_size)); compptr->height_in_blocks = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, (long) (cinfo->max_v_samp_factor * cinfo->block_size)); /* downsampled_width and downsampled_height will also be overridden by * jdmaster.c if we are doing full decompression. The transcoder library * doesn't use these values, but the calling application might. */ /* Size in samples */ compptr->downsampled_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, (long) cinfo->max_h_samp_factor); compptr->downsampled_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, (long) cinfo->max_v_samp_factor); /* Mark component needed, until color conversion says otherwise */ compptr->component_needed = TRUE; /* Mark no quantization table yet saved for component */ compptr->quant_table = NULL; } /* Compute number of fully interleaved MCU rows. */ cinfo->total_iMCU_rows = (JDIMENSION) jdiv_round_up((long) cinfo->image_height, (long) (cinfo->max_v_samp_factor * cinfo->block_size)); /* Decide whether file contains multiple scans */ if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode) cinfo->inputctl->has_multiple_scans = TRUE; else cinfo->inputctl->has_multiple_scans = FALSE;} LOCAL(void)per_scan_setup (j_decompress_ptr cinfo)/* Do computations that are needed before processing a JPEG scan *//* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */{ int ci, mcublks, tmp; jpeg_component_info *compptr; if (cinfo->comps_in_scan == 1) { /* Noninterleaved (single-component) scan */ compptr = cinfo->cur_comp_info[0]; /* Overall image size in MCUs */ cinfo->MCUs_per_row = compptr->width_in_blocks; cinfo->MCU_rows_in_scan = compptr->height_in_blocks; /* For noninterleaved scan, always one block per MCU */ compptr->MCU_width = 1; compptr->MCU_height = 1; compptr->MCU_blocks = 1; compptr->MCU_sample_width = compptr->DCT_h_scaled_size; compptr->last_col_width = 1; /* For noninterleaved scans, it is convenient to define last_row_height * as the number of block rows present in the last iMCU row. */ tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor); if (tmp == 0) tmp = compptr->v_samp_factor; compptr->last_row_height = tmp; /* Prepare array describing MCU composition */ cinfo->blocks_in_MCU = 1; cinfo->MCU_membership[0] = 0; } else { /* Interleaved (multi-component) scan */ if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN) ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan, MAX_COMPS_IN_SCAN); /* Overall image size in MCUs */ cinfo->MCUs_per_row = (JDIMENSION) jdiv_round_up((long) cinfo->image_width, (long) (cinfo->max_h_samp_factor * cinfo->block_size)); cinfo->MCU_rows_in_scan = (JDIMENSION) jdiv_round_up((long) cinfo->image_height, (long) (cinfo->max_v_samp_factor * cinfo->block_size)); cinfo->blocks_in_MCU = 0; for (ci = 0; ci < cinfo->comps_in_scan; ci++) { compptr = cinfo->cur_comp_info[ci]; /* Sampling factors give # of blocks of component in each MCU */ compptr->MCU_width = compptr->h_samp_factor; compptr->MCU_height = compptr->v_samp_factor; compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height; compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_h_scaled_size; /* Figure number of non-dummy blocks in last MCU column & row */ tmp = (int) (compptr->width_in_blocks % compptr->MCU_width); if (tmp == 0) tmp = compptr->MCU_width; compptr->last_col_width = tmp; tmp = (int) (compptr->height_in_blocks % compptr->MCU_height); if (tmp == 0) tmp = compptr->MCU_height; compptr->last_row_height = tmp; /* Prepare array describing MCU composition */ mcublks = compptr->MCU_blocks; if (cinfo->blocks_in_MCU + mcublks > D_MAX_BLOCKS_IN_MCU) ERREXIT(cinfo, JERR_BAD_MCU_SIZE); while (mcublks-- > 0) { cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci; } } }} /* * Save away a copy of the Q-table referenced by each component present * in the current scan, unless already saved during a prior scan. * * In a multiple-scan JPEG file, the encoder could assign different components * the same Q-table slot number, but change table definitions between scans * so that each component uses a different Q-table. (The IJG encoder is not * currently capable of doing this, but other encoders might.) Since we want * to be able to dequantize all the components at the end of the file, this * means that we have to save away the table actually used for each component. * We do this by copying the table at the start of the first scan containing * the component. * The JPEG spec prohibits the encoder from changing the contents of a Q-table * slot between scans of a component using that slot. If the encoder does so * anyway, this decoder will simply use the Q-table values that were current * at the start of the first scan for the component. * * The decompressor output side looks only at the saved quant tables, * not at the current Q-table slots. */ LOCAL(void)latch_quant_tables (j_decompress_ptr cinfo){ int ci, qtblno; jpeg_component_info *compptr; JQUANT_TBL * qtbl; for (ci = 0; ci < cinfo->comps_in_scan; ci++) { compptr = cinfo->cur_comp_info[ci]; /* No work if we already saved Q-table for this component */ if (compptr->quant_table != NULL) continue; /* Make sure specified quantization table is present */ qtblno = compptr->quant_tbl_no; if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||Lines 1–500 of 662. Load more
/* * jdinput.c * * Copyright (C) 1991-1997, Thomas G. Lane. * Modified 2002-2013 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. * * This file contains input control logic for the JPEG decompressor. * These routines are concerned with controlling the decompressor's input * processing (marker reading and coefficient decoding). The actual input * reading is done in jdmarker.c, jdhuff.c, and jdarith.c. */ #define JPEG_INTERNALS #include "jinclude.h" #include "jpeglib.h" /* Private state */ typedef struct { struct jpeg_input_controller pub; /* public fields */ int inheaders; /* Nonzero until first SOS is reached */ } my_input_controller; typedef my_input_controller * my_inputctl_ptr; /* Forward declarations */ METHODDEF(int) consume_markers JPP((j_decompress_ptr cinfo)); /* * Routines to calculate various quantities related to the size of the image. */ /* * Compute output image dimensions and related values. * NOTE: this is exported for possible use by application. * Hence it mustn't do anything that can't be done twice. */ GLOBAL(void) jpeg_core_output_dimensions (j_decompress_ptr cinfo) /* Do computations that are needed before master selection phase. * This function is used for transcoding and full decompression. */ { #ifdef IDCT_SCALING_SUPPORTED int ci; jpeg_component_info *compptr; /* Compute actual output image dimensions and DCT scaling choices. */ if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom) { /* Provide 1/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 1; cinfo->min_DCT_v_scaled_size = 1; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 2) { /* Provide 2/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 2L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 2L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 2; cinfo->min_DCT_v_scaled_size = 2; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 3) { /* Provide 3/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 3L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 3L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 3; cinfo->min_DCT_v_scaled_size = 3; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 4) { /* Provide 4/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 4L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 4L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 4; cinfo->min_DCT_v_scaled_size = 4; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 5) { /* Provide 5/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 5L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 5L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 5; cinfo->min_DCT_v_scaled_size = 5; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 6) { /* Provide 6/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 6L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 6L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 6; cinfo->min_DCT_v_scaled_size = 6; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 7) { /* Provide 7/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 7L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 7L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 7; cinfo->min_DCT_v_scaled_size = 7; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 8) { /* Provide 8/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 8L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 8L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 8; cinfo->min_DCT_v_scaled_size = 8; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 9) { /* Provide 9/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 9L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 9L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 9; cinfo->min_DCT_v_scaled_size = 9; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 10) { /* Provide 10/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 10L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 10L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 10; cinfo->min_DCT_v_scaled_size = 10; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 11) { /* Provide 11/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 11L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 11L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 11; cinfo->min_DCT_v_scaled_size = 11; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 12) { /* Provide 12/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 12L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 12L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 12; cinfo->min_DCT_v_scaled_size = 12; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 13) { /* Provide 13/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 13L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 13L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 13; cinfo->min_DCT_v_scaled_size = 13; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 14) { /* Provide 14/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 14L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 14L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 14; cinfo->min_DCT_v_scaled_size = 14; } else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 15) { /* Provide 15/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 15L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 15L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 15; cinfo->min_DCT_v_scaled_size = 15; } else { /* Provide 16/block_size scaling */ cinfo->output_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * 16L, (long) cinfo->block_size); cinfo->output_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * 16L, (long) cinfo->block_size); cinfo->min_DCT_h_scaled_size = 16; cinfo->min_DCT_v_scaled_size = 16; } /* Recompute dimensions of components */ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size; compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size; } #else /* !IDCT_SCALING_SUPPORTED */ /* Hardwire it to "no scaling" */ cinfo->output_width = cinfo->image_width; cinfo->output_height = cinfo->image_height; /* initial_setup has already initialized DCT_scaled_size, * and has computed unscaled downsampled_width and downsampled_height. */ #endif /* IDCT_SCALING_SUPPORTED */ } LOCAL(void) initial_setup (j_decompress_ptr cinfo) /* Called once, when first SOS marker is reached */ { int ci; jpeg_component_info *compptr; /* Make sure image isn't bigger than I can handle */ if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION || (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION) ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION); /* Only 8 to 12 bits data precision are supported for DCT based JPEG */ if (cinfo->data_precision < 8 || cinfo->data_precision > 12) ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); /* Check that number of components won't exceed internal array sizes */ if (cinfo->num_components > MAX_COMPONENTS) ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, MAX_COMPONENTS); /* Compute maximum sampling factors; check factor validity */ cinfo->max_h_samp_factor = 1; cinfo->max_v_samp_factor = 1; for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR || compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR) ERREXIT(cinfo, JERR_BAD_SAMPLING); cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor, compptr->h_samp_factor); cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor, compptr->v_samp_factor); } /* Derive block_size, natural_order, and lim_Se */ if (cinfo->is_baseline || (cinfo->progressive_mode && cinfo->comps_in_scan)) { /* no pseudo SOS marker */ cinfo->block_size = DCTSIZE; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; } else switch (cinfo->Se) { case (1*1-1): cinfo->block_size = 1; cinfo->natural_order = jpeg_natural_order; /* not needed */ cinfo->lim_Se = cinfo->Se; break; case (2*2-1): cinfo->block_size = 2; cinfo->natural_order = jpeg_natural_order2; cinfo->lim_Se = cinfo->Se; break; case (3*3-1): cinfo->block_size = 3; cinfo->natural_order = jpeg_natural_order3; cinfo->lim_Se = cinfo->Se; break; case (4*4-1): cinfo->block_size = 4; cinfo->natural_order = jpeg_natural_order4; cinfo->lim_Se = cinfo->Se; break; case (5*5-1): cinfo->block_size = 5; cinfo->natural_order = jpeg_natural_order5; cinfo->lim_Se = cinfo->Se; break; case (6*6-1): cinfo->block_size = 6; cinfo->natural_order = jpeg_natural_order6; cinfo->lim_Se = cinfo->Se; break; case (7*7-1): cinfo->block_size = 7; cinfo->natural_order = jpeg_natural_order7; cinfo->lim_Se = cinfo->Se; break; case (8*8-1): cinfo->block_size = 8; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (9*9-1): cinfo->block_size = 9; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (10*10-1): cinfo->block_size = 10; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (11*11-1): cinfo->block_size = 11; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (12*12-1): cinfo->block_size = 12; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (13*13-1): cinfo->block_size = 13; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (14*14-1): cinfo->block_size = 14; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (15*15-1): cinfo->block_size = 15; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; case (16*16-1): cinfo->block_size = 16; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; break; default: ERREXIT4(cinfo, JERR_BAD_PROGRESSION, cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al); break; } /* We initialize DCT_scaled_size and min_DCT_scaled_size to block_size. * In the full decompressor, * this will be overridden by jpeg_calc_output_dimensions in jdmaster.c; * but in the transcoder, * jpeg_calc_output_dimensions is not used, so we must do it here. */ cinfo->min_DCT_h_scaled_size = cinfo->block_size; cinfo->min_DCT_v_scaled_size = cinfo->block_size; /* Compute dimensions of components */ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { compptr->DCT_h_scaled_size = cinfo->block_size; compptr->DCT_v_scaled_size = cinfo->block_size; /* Size in DCT blocks */ compptr->width_in_blocks = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, (long) (cinfo->max_h_samp_factor * cinfo->block_size)); compptr->height_in_blocks = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, (long) (cinfo->max_v_samp_factor * cinfo->block_size)); /* downsampled_width and downsampled_height will also be overridden by * jdmaster.c if we are doing full decompression. The transcoder library * doesn't use these values, but the calling application might. */ /* Size in samples */ compptr->downsampled_width = (JDIMENSION) jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, (long) cinfo->max_h_samp_factor); compptr->downsampled_height = (JDIMENSION) jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, (long) cinfo->max_v_samp_factor); /* Mark component needed, until color conversion says otherwise */ compptr->component_needed = TRUE; /* Mark no quantization table yet saved for component */ compptr->quant_table = NULL; } /* Compute number of fully interleaved MCU rows. */ cinfo->total_iMCU_rows = (JDIMENSION) jdiv_round_up((long) cinfo->image_height, (long) (cinfo->max_v_samp_factor * cinfo->block_size)); /* Decide whether file contains multiple scans */ if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode) cinfo->inputctl->has_multiple_scans = TRUE; else cinfo->inputctl->has_multiple_scans = FALSE; } LOCAL(void) per_scan_setup (j_decompress_ptr cinfo) /* Do computations that are needed before processing a JPEG scan */ /* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */ { int ci, mcublks, tmp; jpeg_component_info *compptr; if (cinfo->comps_in_scan == 1) { /* Noninterleaved (single-component) scan */ compptr = cinfo->cur_comp_info[0]; /* Overall image size in MCUs */ cinfo->MCUs_per_row = compptr->width_in_blocks; cinfo->MCU_rows_in_scan = compptr->height_in_blocks; /* For noninterleaved scan, always one block per MCU */ compptr->MCU_width = 1; compptr->MCU_height = 1; compptr->MCU_blocks = 1; compptr->MCU_sample_width = compptr->DCT_h_scaled_size; compptr->last_col_width = 1; /* For noninterleaved scans, it is convenient to define last_row_height * as the number of block rows present in the last iMCU row. */ tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor); if (tmp == 0) tmp = compptr->v_samp_factor; compptr->last_row_height = tmp; /* Prepare array describing MCU composition */ cinfo->blocks_in_MCU = 1; cinfo->MCU_membership[0] = 0; } else { /* Interleaved (multi-component) scan */ if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN) ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan, MAX_COMPS_IN_SCAN); /* Overall image size in MCUs */ cinfo->MCUs_per_row = (JDIMENSION) jdiv_round_up((long) cinfo->image_width, (long) (cinfo->max_h_samp_factor * cinfo->block_size)); cinfo->MCU_rows_in_scan = (JDIMENSION) jdiv_round_up((long) cinfo->image_height, (long) (cinfo->max_v_samp_factor * cinfo->block_size)); cinfo->blocks_in_MCU = 0; for (ci = 0; ci < cinfo->comps_in_scan; ci++) { compptr = cinfo->cur_comp_info[ci]; /* Sampling factors give # of blocks of component in each MCU */ compptr->MCU_width = compptr->h_samp_factor; compptr->MCU_height = compptr->v_samp_factor; compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height; compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_h_scaled_size; /* Figure number of non-dummy blocks in last MCU column & row */ tmp = (int) (compptr->width_in_blocks % compptr->MCU_width); if (tmp == 0) tmp = compptr->MCU_width; compptr->last_col_width = tmp; tmp = (int) (compptr->height_in_blocks % compptr->MCU_height); if (tmp == 0) tmp = compptr->MCU_height; compptr->last_row_height = tmp; /* Prepare array describing MCU composition */ mcublks = compptr->MCU_blocks; if (cinfo->blocks_in_MCU + mcublks > D_MAX_BLOCKS_IN_MCU) ERREXIT(cinfo, JERR_BAD_MCU_SIZE); while (mcublks-- > 0) { cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci; } } } } /* * Save away a copy of the Q-table referenced by each component present * in the current scan, unless already saved during a prior scan. * * In a multiple-scan JPEG file, the encoder could assign different components * the same Q-table slot number, but change table definitions between scans * so that each component uses a different Q-table. (The IJG encoder is not * currently capable of doing this, but other encoders might.) Since we want * to be able to dequantize all the components at the end of the file, this * means that we have to save away the table actually used for each component. * We do this by copying the table at the start of the first scan containing * the component. * The JPEG spec prohibits the encoder from changing the contents of a Q-table * slot between scans of a component using that slot. If the encoder does so * anyway, this decoder will simply use the Q-table values that were current * at the start of the first scan for the component. * * The decompressor output side looks only at the saved quant tables, * not at the current Q-table slots. */ LOCAL(void) latch_quant_tables (j_decompress_ptr cinfo) { int ci, qtblno; jpeg_component_info *compptr; JQUANT_TBL * qtbl; for (ci = 0; ci < cinfo->comps_in_scan; ci++) { compptr = cinfo->cur_comp_info[ci]; /* No work if we already saved Q-table for this component */ if (compptr->quant_table != NULL) continue; /* Make sure specified quantization table is present */ qtblno = compptr->quant_tbl_no; if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||