vrshoot

diff libs/libjpeg/jctrans.c @ 0:b2f14e535253

initial commit
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 01 Feb 2014 19:58:19 +0200
parents
children
line diff
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libs/libjpeg/jctrans.c	Sat Feb 01 19:58:19 2014 +0200
     1.3 @@ -0,0 +1,388 @@
     1.4 +/*
     1.5 + * jctrans.c
     1.6 + *
     1.7 + * Copyright (C) 1995-1998, Thomas G. Lane.
     1.8 + * This file is part of the Independent JPEG Group's software.
     1.9 + * For conditions of distribution and use, see the accompanying README file.
    1.10 + *
    1.11 + * This file contains library routines for transcoding compression,
    1.12 + * that is, writing raw DCT coefficient arrays to an output JPEG file.
    1.13 + * The routines in jcapimin.c will also be needed by a transcoder.
    1.14 + */
    1.15 +
    1.16 +#define JPEG_INTERNALS
    1.17 +#include "jinclude.h"
    1.18 +#include "jpeglib.h"
    1.19 +
    1.20 +
    1.21 +/* Forward declarations */
    1.22 +LOCAL(void) transencode_master_selection
    1.23 +	JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));
    1.24 +LOCAL(void) transencode_coef_controller
    1.25 +	JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));
    1.26 +
    1.27 +
    1.28 +/*
    1.29 + * Compression initialization for writing raw-coefficient data.
    1.30 + * Before calling this, all parameters and a data destination must be set up.
    1.31 + * Call jpeg_finish_compress() to actually write the data.
    1.32 + *
    1.33 + * The number of passed virtual arrays must match cinfo->num_components.
    1.34 + * Note that the virtual arrays need not be filled or even realized at
    1.35 + * the time write_coefficients is called; indeed, if the virtual arrays
    1.36 + * were requested from this compression object's memory manager, they
    1.37 + * typically will be realized during this routine and filled afterwards.
    1.38 + */
    1.39 +
    1.40 +GLOBAL(void)
    1.41 +jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)
    1.42 +{
    1.43 +  if (cinfo->global_state != CSTATE_START)
    1.44 +    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
    1.45 +  /* Mark all tables to be written */
    1.46 +  jpeg_suppress_tables(cinfo, FALSE);
    1.47 +  /* (Re)initialize error mgr and destination modules */
    1.48 +  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
    1.49 +  (*cinfo->dest->init_destination) (cinfo);
    1.50 +  /* Perform master selection of active modules */
    1.51 +  transencode_master_selection(cinfo, coef_arrays);
    1.52 +  /* Wait for jpeg_finish_compress() call */
    1.53 +  cinfo->next_scanline = 0;	/* so jpeg_write_marker works */
    1.54 +  cinfo->global_state = CSTATE_WRCOEFS;
    1.55 +}
    1.56 +
    1.57 +
    1.58 +/*
    1.59 + * Initialize the compression object with default parameters,
    1.60 + * then copy from the source object all parameters needed for lossless
    1.61 + * transcoding.  Parameters that can be varied without loss (such as
    1.62 + * scan script and Huffman optimization) are left in their default states.
    1.63 + */
    1.64 +
    1.65 +GLOBAL(void)
    1.66 +jpeg_copy_critical_parameters (j_decompress_ptr srcinfo,
    1.67 +			       j_compress_ptr dstinfo)
    1.68 +{
    1.69 +  JQUANT_TBL ** qtblptr;
    1.70 +  jpeg_component_info *incomp, *outcomp;
    1.71 +  JQUANT_TBL *c_quant, *slot_quant;
    1.72 +  int tblno, ci, coefi;
    1.73 +
    1.74 +  /* Safety check to ensure start_compress not called yet. */
    1.75 +  if (dstinfo->global_state != CSTATE_START)
    1.76 +    ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state);
    1.77 +  /* Copy fundamental image dimensions */
    1.78 +  dstinfo->image_width = srcinfo->image_width;
    1.79 +  dstinfo->image_height = srcinfo->image_height;
    1.80 +  dstinfo->input_components = srcinfo->num_components;
    1.81 +  dstinfo->in_color_space = srcinfo->jpeg_color_space;
    1.82 +  /* Initialize all parameters to default values */
    1.83 +  jpeg_set_defaults(dstinfo);
    1.84 +  /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB.
    1.85 +   * Fix it to get the right header markers for the image colorspace.
    1.86 +   */
    1.87 +  jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space);
    1.88 +  dstinfo->data_precision = srcinfo->data_precision;
    1.89 +  dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling;
    1.90 +  /* Copy the source's quantization tables. */
    1.91 +  for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
    1.92 +    if (srcinfo->quant_tbl_ptrs[tblno] != NULL) {
    1.93 +      qtblptr = & dstinfo->quant_tbl_ptrs[tblno];
    1.94 +      if (*qtblptr == NULL)
    1.95 +	*qtblptr = jpeg_alloc_quant_table((j_common_ptr) dstinfo);
    1.96 +      MEMCOPY((*qtblptr)->quantval,
    1.97 +	      srcinfo->quant_tbl_ptrs[tblno]->quantval,
    1.98 +	      SIZEOF((*qtblptr)->quantval));
    1.99 +      (*qtblptr)->sent_table = FALSE;
   1.100 +    }
   1.101 +  }
   1.102 +  /* Copy the source's per-component info.
   1.103 +   * Note we assume jpeg_set_defaults has allocated the dest comp_info array.
   1.104 +   */
   1.105 +  dstinfo->num_components = srcinfo->num_components;
   1.106 +  if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS)
   1.107 +    ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components,
   1.108 +	     MAX_COMPONENTS);
   1.109 +  for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info;
   1.110 +       ci < dstinfo->num_components; ci++, incomp++, outcomp++) {
   1.111 +    outcomp->component_id = incomp->component_id;
   1.112 +    outcomp->h_samp_factor = incomp->h_samp_factor;
   1.113 +    outcomp->v_samp_factor = incomp->v_samp_factor;
   1.114 +    outcomp->quant_tbl_no = incomp->quant_tbl_no;
   1.115 +    /* Make sure saved quantization table for component matches the qtable
   1.116 +     * slot.  If not, the input file re-used this qtable slot.
   1.117 +     * IJG encoder currently cannot duplicate this.
   1.118 +     */
   1.119 +    tblno = outcomp->quant_tbl_no;
   1.120 +    if (tblno < 0 || tblno >= NUM_QUANT_TBLS ||
   1.121 +	srcinfo->quant_tbl_ptrs[tblno] == NULL)
   1.122 +      ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno);
   1.123 +    slot_quant = srcinfo->quant_tbl_ptrs[tblno];
   1.124 +    c_quant = incomp->quant_table;
   1.125 +    if (c_quant != NULL) {
   1.126 +      for (coefi = 0; coefi < DCTSIZE2; coefi++) {
   1.127 +	if (c_quant->quantval[coefi] != slot_quant->quantval[coefi])
   1.128 +	  ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno);
   1.129 +      }
   1.130 +    }
   1.131 +    /* Note: we do not copy the source's Huffman table assignments;
   1.132 +     * instead we rely on jpeg_set_colorspace to have made a suitable choice.
   1.133 +     */
   1.134 +  }
   1.135 +  /* Also copy JFIF version and resolution information, if available.
   1.136 +   * Strictly speaking this isn't "critical" info, but it's nearly
   1.137 +   * always appropriate to copy it if available.  In particular,
   1.138 +   * if the application chooses to copy JFIF 1.02 extension markers from
   1.139 +   * the source file, we need to copy the version to make sure we don't
   1.140 +   * emit a file that has 1.02 extensions but a claimed version of 1.01.
   1.141 +   * We will *not*, however, copy version info from mislabeled "2.01" files.
   1.142 +   */
   1.143 +  if (srcinfo->saw_JFIF_marker) {
   1.144 +    if (srcinfo->JFIF_major_version == 1) {
   1.145 +      dstinfo->JFIF_major_version = srcinfo->JFIF_major_version;
   1.146 +      dstinfo->JFIF_minor_version = srcinfo->JFIF_minor_version;
   1.147 +    }
   1.148 +    dstinfo->density_unit = srcinfo->density_unit;
   1.149 +    dstinfo->X_density = srcinfo->X_density;
   1.150 +    dstinfo->Y_density = srcinfo->Y_density;
   1.151 +  }
   1.152 +}
   1.153 +
   1.154 +
   1.155 +/*
   1.156 + * Master selection of compression modules for transcoding.
   1.157 + * This substitutes for jcinit.c's initialization of the full compressor.
   1.158 + */
   1.159 +
   1.160 +LOCAL(void)
   1.161 +transencode_master_selection (j_compress_ptr cinfo,
   1.162 +			      jvirt_barray_ptr * coef_arrays)
   1.163 +{
   1.164 +  /* Although we don't actually use input_components for transcoding,
   1.165 +   * jcmaster.c's initial_setup will complain if input_components is 0.
   1.166 +   */
   1.167 +  cinfo->input_components = 1;
   1.168 +  /* Initialize master control (includes parameter checking/processing) */
   1.169 +  jinit_c_master_control(cinfo, TRUE /* transcode only */);
   1.170 +
   1.171 +  /* Entropy encoding: either Huffman or arithmetic coding. */
   1.172 +  if (cinfo->arith_code) {
   1.173 +    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
   1.174 +  } else {
   1.175 +    if (cinfo->progressive_mode) {
   1.176 +#ifdef C_PROGRESSIVE_SUPPORTED
   1.177 +      jinit_phuff_encoder(cinfo);
   1.178 +#else
   1.179 +      ERREXIT(cinfo, JERR_NOT_COMPILED);
   1.180 +#endif
   1.181 +    } else
   1.182 +      jinit_huff_encoder(cinfo);
   1.183 +  }
   1.184 +
   1.185 +  /* We need a special coefficient buffer controller. */
   1.186 +  transencode_coef_controller(cinfo, coef_arrays);
   1.187 +
   1.188 +  jinit_marker_writer(cinfo);
   1.189 +
   1.190 +  /* We can now tell the memory manager to allocate virtual arrays. */
   1.191 +  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
   1.192 +
   1.193 +  /* Write the datastream header (SOI, JFIF) immediately.
   1.194 +   * Frame and scan headers are postponed till later.
   1.195 +   * This lets application insert special markers after the SOI.
   1.196 +   */
   1.197 +  (*cinfo->marker->write_file_header) (cinfo);
   1.198 +}
   1.199 +
   1.200 +
   1.201 +/*
   1.202 + * The rest of this file is a special implementation of the coefficient
   1.203 + * buffer controller.  This is similar to jccoefct.c, but it handles only
   1.204 + * output from presupplied virtual arrays.  Furthermore, we generate any
   1.205 + * dummy padding blocks on-the-fly rather than expecting them to be present
   1.206 + * in the arrays.
   1.207 + */
   1.208 +
   1.209 +/* Private buffer controller object */
   1.210 +
   1.211 +typedef struct {
   1.212 +  struct jpeg_c_coef_controller pub; /* public fields */
   1.213 +
   1.214 +  JDIMENSION iMCU_row_num;	/* iMCU row # within image */
   1.215 +  JDIMENSION mcu_ctr;		/* counts MCUs processed in current row */
   1.216 +  int MCU_vert_offset;		/* counts MCU rows within iMCU row */
   1.217 +  int MCU_rows_per_iMCU_row;	/* number of such rows needed */
   1.218 +
   1.219 +  /* Virtual block array for each component. */
   1.220 +  jvirt_barray_ptr * whole_image;
   1.221 +
   1.222 +  /* Workspace for constructing dummy blocks at right/bottom edges. */
   1.223 +  JBLOCKROW dummy_buffer[C_MAX_BLOCKS_IN_MCU];
   1.224 +} my_coef_controller;
   1.225 +
   1.226 +typedef my_coef_controller * my_coef_ptr;
   1.227 +
   1.228 +
   1.229 +LOCAL(void)
   1.230 +start_iMCU_row (j_compress_ptr cinfo)
   1.231 +/* Reset within-iMCU-row counters for a new row */
   1.232 +{
   1.233 +  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
   1.234 +
   1.235 +  /* In an interleaved scan, an MCU row is the same as an iMCU row.
   1.236 +   * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.
   1.237 +   * But at the bottom of the image, process only what's left.
   1.238 +   */
   1.239 +  if (cinfo->comps_in_scan > 1) {
   1.240 +    coef->MCU_rows_per_iMCU_row = 1;
   1.241 +  } else {
   1.242 +    if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1))
   1.243 +      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;
   1.244 +    else
   1.245 +      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;
   1.246 +  }
   1.247 +
   1.248 +  coef->mcu_ctr = 0;
   1.249 +  coef->MCU_vert_offset = 0;
   1.250 +}
   1.251 +
   1.252 +
   1.253 +/*
   1.254 + * Initialize for a processing pass.
   1.255 + */
   1.256 +
   1.257 +METHODDEF(void)
   1.258 +start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
   1.259 +{
   1.260 +  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
   1.261 +
   1.262 +  if (pass_mode != JBUF_CRANK_DEST)
   1.263 +    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
   1.264 +
   1.265 +  coef->iMCU_row_num = 0;
   1.266 +  start_iMCU_row(cinfo);
   1.267 +}
   1.268 +
   1.269 +
   1.270 +/*
   1.271 + * Process some data.
   1.272 + * We process the equivalent of one fully interleaved MCU row ("iMCU" row)
   1.273 + * per call, ie, v_samp_factor block rows for each component in the scan.
   1.274 + * The data is obtained from the virtual arrays and fed to the entropy coder.
   1.275 + * Returns TRUE if the iMCU row is completed, FALSE if suspended.
   1.276 + *
   1.277 + * NB: input_buf is ignored; it is likely to be a NULL pointer.
   1.278 + */
   1.279 +
   1.280 +METHODDEF(boolean)
   1.281 +compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf)
   1.282 +{
   1.283 +  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
   1.284 +  JDIMENSION MCU_col_num;	/* index of current MCU within row */
   1.285 +  JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;
   1.286 +  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
   1.287 +  int blkn, ci, xindex, yindex, yoffset, blockcnt;
   1.288 +  JDIMENSION start_col;
   1.289 +  JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];
   1.290 +  JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];
   1.291 +  JBLOCKROW buffer_ptr;
   1.292 +  jpeg_component_info *compptr;
   1.293 +
   1.294 +  /* Align the virtual buffers for the components used in this scan. */
   1.295 +  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
   1.296 +    compptr = cinfo->cur_comp_info[ci];
   1.297 +    buffer[ci] = (*cinfo->mem->access_virt_barray)
   1.298 +      ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],
   1.299 +       coef->iMCU_row_num * compptr->v_samp_factor,
   1.300 +       (JDIMENSION) compptr->v_samp_factor, FALSE);
   1.301 +  }
   1.302 +
   1.303 +  /* Loop to process one whole iMCU row */
   1.304 +  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;
   1.305 +       yoffset++) {
   1.306 +    for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row;
   1.307 +	 MCU_col_num++) {
   1.308 +      /* Construct list of pointers to DCT blocks belonging to this MCU */
   1.309 +      blkn = 0;			/* index of current DCT block within MCU */
   1.310 +      for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
   1.311 +	compptr = cinfo->cur_comp_info[ci];
   1.312 +	start_col = MCU_col_num * compptr->MCU_width;
   1.313 +	blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width
   1.314 +						: compptr->last_col_width;
   1.315 +	for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
   1.316 +	  if (coef->iMCU_row_num < last_iMCU_row ||
   1.317 +	      yindex+yoffset < compptr->last_row_height) {
   1.318 +	    /* Fill in pointers to real blocks in this row */
   1.319 +	    buffer_ptr = buffer[ci][yindex+yoffset] + start_col;
   1.320 +	    for (xindex = 0; xindex < blockcnt; xindex++)
   1.321 +	      MCU_buffer[blkn++] = buffer_ptr++;
   1.322 +	  } else {
   1.323 +	    /* At bottom of image, need a whole row of dummy blocks */
   1.324 +	    xindex = 0;
   1.325 +	  }
   1.326 +	  /* Fill in any dummy blocks needed in this row.
   1.327 +	   * Dummy blocks are filled in the same way as in jccoefct.c:
   1.328 +	   * all zeroes in the AC entries, DC entries equal to previous
   1.329 +	   * block's DC value.  The init routine has already zeroed the
   1.330 +	   * AC entries, so we need only set the DC entries correctly.
   1.331 +	   */
   1.332 +	  for (; xindex < compptr->MCU_width; xindex++) {
   1.333 +	    MCU_buffer[blkn] = coef->dummy_buffer[blkn];
   1.334 +	    MCU_buffer[blkn][0][0] = MCU_buffer[blkn-1][0][0];
   1.335 +	    blkn++;
   1.336 +	  }
   1.337 +	}
   1.338 +      }
   1.339 +      /* Try to write the MCU. */
   1.340 +      if (! (*cinfo->entropy->encode_mcu) (cinfo, MCU_buffer)) {
   1.341 +	/* Suspension forced; update state counters and exit */
   1.342 +	coef->MCU_vert_offset = yoffset;
   1.343 +	coef->mcu_ctr = MCU_col_num;
   1.344 +	return FALSE;
   1.345 +      }
   1.346 +    }
   1.347 +    /* Completed an MCU row, but perhaps not an iMCU row */
   1.348 +    coef->mcu_ctr = 0;
   1.349 +  }
   1.350 +  /* Completed the iMCU row, advance counters for next one */
   1.351 +  coef->iMCU_row_num++;
   1.352 +  start_iMCU_row(cinfo);
   1.353 +  return TRUE;
   1.354 +}
   1.355 +
   1.356 +
   1.357 +/*
   1.358 + * Initialize coefficient buffer controller.
   1.359 + *
   1.360 + * Each passed coefficient array must be the right size for that
   1.361 + * coefficient: width_in_blocks wide and height_in_blocks high,
   1.362 + * with unitheight at least v_samp_factor.
   1.363 + */
   1.364 +
   1.365 +LOCAL(void)
   1.366 +transencode_coef_controller (j_compress_ptr cinfo,
   1.367 +			     jvirt_barray_ptr * coef_arrays)
   1.368 +{
   1.369 +  my_coef_ptr coef;
   1.370 +  JBLOCKROW buffer;
   1.371 +  int i;
   1.372 +
   1.373 +  coef = (my_coef_ptr)
   1.374 +    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
   1.375 +				SIZEOF(my_coef_controller));
   1.376 +  cinfo->coef = (struct jpeg_c_coef_controller *) coef;
   1.377 +  coef->pub.start_pass = start_pass_coef;
   1.378 +  coef->pub.compress_data = compress_output;
   1.379 +
   1.380 +  /* Save pointer to virtual arrays */
   1.381 +  coef->whole_image = coef_arrays;
   1.382 +
   1.383 +  /* Allocate and pre-zero space for dummy DCT blocks. */
   1.384 +  buffer = (JBLOCKROW)
   1.385 +    (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
   1.386 +				C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
   1.387 +  jzero_far((void FAR *) buffer, C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
   1.388 +  for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {
   1.389 +    coef->dummy_buffer[i] = buffer + i;
   1.390 +  }
   1.391 +}