vrshoot

diff libs/libjpeg/jcmainct.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/jcmainct.c	Sat Feb 01 19:58:19 2014 +0200
     1.3 @@ -0,0 +1,293 @@
     1.4 +/*
     1.5 + * jcmainct.c
     1.6 + *
     1.7 + * Copyright (C) 1994-1996, 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 the main buffer controller for compression.
    1.12 + * The main buffer lies between the pre-processor and the JPEG
    1.13 + * compressor proper; it holds downsampled data in the JPEG colorspace.
    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 +/* Note: currently, there is no operating mode in which a full-image buffer
    1.22 + * is needed at this step.  If there were, that mode could not be used with
    1.23 + * "raw data" input, since this module is bypassed in that case.  However,
    1.24 + * we've left the code here for possible use in special applications.
    1.25 + */
    1.26 +#undef FULL_MAIN_BUFFER_SUPPORTED
    1.27 +
    1.28 +
    1.29 +/* Private buffer controller object */
    1.30 +
    1.31 +typedef struct {
    1.32 +  struct jpeg_c_main_controller pub; /* public fields */
    1.33 +
    1.34 +  JDIMENSION cur_iMCU_row;	/* number of current iMCU row */
    1.35 +  JDIMENSION rowgroup_ctr;	/* counts row groups received in iMCU row */
    1.36 +  boolean suspended;		/* remember if we suspended output */
    1.37 +  J_BUF_MODE pass_mode;		/* current operating mode */
    1.38 +
    1.39 +  /* If using just a strip buffer, this points to the entire set of buffers
    1.40 +   * (we allocate one for each component).  In the full-image case, this
    1.41 +   * points to the currently accessible strips of the virtual arrays.
    1.42 +   */
    1.43 +  JSAMPARRAY buffer[MAX_COMPONENTS];
    1.44 +
    1.45 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
    1.46 +  /* If using full-image storage, this array holds pointers to virtual-array
    1.47 +   * control blocks for each component.  Unused if not full-image storage.
    1.48 +   */
    1.49 +  jvirt_sarray_ptr whole_image[MAX_COMPONENTS];
    1.50 +#endif
    1.51 +} my_main_controller;
    1.52 +
    1.53 +typedef my_main_controller * my_main_ptr;
    1.54 +
    1.55 +
    1.56 +/* Forward declarations */
    1.57 +METHODDEF(void) process_data_simple_main
    1.58 +	JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,
    1.59 +	     JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));
    1.60 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
    1.61 +METHODDEF(void) process_data_buffer_main
    1.62 +	JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,
    1.63 +	     JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));
    1.64 +#endif
    1.65 +
    1.66 +
    1.67 +/*
    1.68 + * Initialize for a processing pass.
    1.69 + */
    1.70 +
    1.71 +METHODDEF(void)
    1.72 +start_pass_main (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
    1.73 +{
    1.74 +  my_main_ptr main = (my_main_ptr) cinfo->main;
    1.75 +
    1.76 +  /* Do nothing in raw-data mode. */
    1.77 +  if (cinfo->raw_data_in)
    1.78 +    return;
    1.79 +
    1.80 +  main->cur_iMCU_row = 0;	/* initialize counters */
    1.81 +  main->rowgroup_ctr = 0;
    1.82 +  main->suspended = FALSE;
    1.83 +  main->pass_mode = pass_mode;	/* save mode for use by process_data */
    1.84 +
    1.85 +  switch (pass_mode) {
    1.86 +  case JBUF_PASS_THRU:
    1.87 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
    1.88 +    if (main->whole_image[0] != NULL)
    1.89 +      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
    1.90 +#endif
    1.91 +    main->pub.process_data = process_data_simple_main;
    1.92 +    break;
    1.93 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
    1.94 +  case JBUF_SAVE_SOURCE:
    1.95 +  case JBUF_CRANK_DEST:
    1.96 +  case JBUF_SAVE_AND_PASS:
    1.97 +    if (main->whole_image[0] == NULL)
    1.98 +      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
    1.99 +    main->pub.process_data = process_data_buffer_main;
   1.100 +    break;
   1.101 +#endif
   1.102 +  default:
   1.103 +    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
   1.104 +    break;
   1.105 +  }
   1.106 +}
   1.107 +
   1.108 +
   1.109 +/*
   1.110 + * Process some data.
   1.111 + * This routine handles the simple pass-through mode,
   1.112 + * where we have only a strip buffer.
   1.113 + */
   1.114 +
   1.115 +METHODDEF(void)
   1.116 +process_data_simple_main (j_compress_ptr cinfo,
   1.117 +			  JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
   1.118 +			  JDIMENSION in_rows_avail)
   1.119 +{
   1.120 +  my_main_ptr main = (my_main_ptr) cinfo->main;
   1.121 +
   1.122 +  while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {
   1.123 +    /* Read input data if we haven't filled the main buffer yet */
   1.124 +    if (main->rowgroup_ctr < DCTSIZE)
   1.125 +      (*cinfo->prep->pre_process_data) (cinfo,
   1.126 +					input_buf, in_row_ctr, in_rows_avail,
   1.127 +					main->buffer, &main->rowgroup_ctr,
   1.128 +					(JDIMENSION) DCTSIZE);
   1.129 +
   1.130 +    /* If we don't have a full iMCU row buffered, return to application for
   1.131 +     * more data.  Note that preprocessor will always pad to fill the iMCU row
   1.132 +     * at the bottom of the image.
   1.133 +     */
   1.134 +    if (main->rowgroup_ctr != DCTSIZE)
   1.135 +      return;
   1.136 +
   1.137 +    /* Send the completed row to the compressor */
   1.138 +    if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {
   1.139 +      /* If compressor did not consume the whole row, then we must need to
   1.140 +       * suspend processing and return to the application.  In this situation
   1.141 +       * we pretend we didn't yet consume the last input row; otherwise, if
   1.142 +       * it happened to be the last row of the image, the application would
   1.143 +       * think we were done.
   1.144 +       */
   1.145 +      if (! main->suspended) {
   1.146 +	(*in_row_ctr)--;
   1.147 +	main->suspended = TRUE;
   1.148 +      }
   1.149 +      return;
   1.150 +    }
   1.151 +    /* We did finish the row.  Undo our little suspension hack if a previous
   1.152 +     * call suspended; then mark the main buffer empty.
   1.153 +     */
   1.154 +    if (main->suspended) {
   1.155 +      (*in_row_ctr)++;
   1.156 +      main->suspended = FALSE;
   1.157 +    }
   1.158 +    main->rowgroup_ctr = 0;
   1.159 +    main->cur_iMCU_row++;
   1.160 +  }
   1.161 +}
   1.162 +
   1.163 +
   1.164 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
   1.165 +
   1.166 +/*
   1.167 + * Process some data.
   1.168 + * This routine handles all of the modes that use a full-size buffer.
   1.169 + */
   1.170 +
   1.171 +METHODDEF(void)
   1.172 +process_data_buffer_main (j_compress_ptr cinfo,
   1.173 +			  JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
   1.174 +			  JDIMENSION in_rows_avail)
   1.175 +{
   1.176 +  my_main_ptr main = (my_main_ptr) cinfo->main;
   1.177 +  int ci;
   1.178 +  jpeg_component_info *compptr;
   1.179 +  boolean writing = (main->pass_mode != JBUF_CRANK_DEST);
   1.180 +
   1.181 +  while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {
   1.182 +    /* Realign the virtual buffers if at the start of an iMCU row. */
   1.183 +    if (main->rowgroup_ctr == 0) {
   1.184 +      for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
   1.185 +	   ci++, compptr++) {
   1.186 +	main->buffer[ci] = (*cinfo->mem->access_virt_sarray)
   1.187 +	  ((j_common_ptr) cinfo, main->whole_image[ci],
   1.188 +	   main->cur_iMCU_row * (compptr->v_samp_factor * DCTSIZE),
   1.189 +	   (JDIMENSION) (compptr->v_samp_factor * DCTSIZE), writing);
   1.190 +      }
   1.191 +      /* In a read pass, pretend we just read some source data. */
   1.192 +      if (! writing) {
   1.193 +	*in_row_ctr += cinfo->max_v_samp_factor * DCTSIZE;
   1.194 +	main->rowgroup_ctr = DCTSIZE;
   1.195 +      }
   1.196 +    }
   1.197 +
   1.198 +    /* If a write pass, read input data until the current iMCU row is full. */
   1.199 +    /* Note: preprocessor will pad if necessary to fill the last iMCU row. */
   1.200 +    if (writing) {
   1.201 +      (*cinfo->prep->pre_process_data) (cinfo,
   1.202 +					input_buf, in_row_ctr, in_rows_avail,
   1.203 +					main->buffer, &main->rowgroup_ctr,
   1.204 +					(JDIMENSION) DCTSIZE);
   1.205 +      /* Return to application if we need more data to fill the iMCU row. */
   1.206 +      if (main->rowgroup_ctr < DCTSIZE)
   1.207 +	return;
   1.208 +    }
   1.209 +
   1.210 +    /* Emit data, unless this is a sink-only pass. */
   1.211 +    if (main->pass_mode != JBUF_SAVE_SOURCE) {
   1.212 +      if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {
   1.213 +	/* If compressor did not consume the whole row, then we must need to
   1.214 +	 * suspend processing and return to the application.  In this situation
   1.215 +	 * we pretend we didn't yet consume the last input row; otherwise, if
   1.216 +	 * it happened to be the last row of the image, the application would
   1.217 +	 * think we were done.
   1.218 +	 */
   1.219 +	if (! main->suspended) {
   1.220 +	  (*in_row_ctr)--;
   1.221 +	  main->suspended = TRUE;
   1.222 +	}
   1.223 +	return;
   1.224 +      }
   1.225 +      /* We did finish the row.  Undo our little suspension hack if a previous
   1.226 +       * call suspended; then mark the main buffer empty.
   1.227 +       */
   1.228 +      if (main->suspended) {
   1.229 +	(*in_row_ctr)++;
   1.230 +	main->suspended = FALSE;
   1.231 +      }
   1.232 +    }
   1.233 +
   1.234 +    /* If get here, we are done with this iMCU row.  Mark buffer empty. */
   1.235 +    main->rowgroup_ctr = 0;
   1.236 +    main->cur_iMCU_row++;
   1.237 +  }
   1.238 +}
   1.239 +
   1.240 +#endif /* FULL_MAIN_BUFFER_SUPPORTED */
   1.241 +
   1.242 +
   1.243 +/*
   1.244 + * Initialize main buffer controller.
   1.245 + */
   1.246 +
   1.247 +GLOBAL(void)
   1.248 +jinit_c_main_controller (j_compress_ptr cinfo, boolean need_full_buffer)
   1.249 +{
   1.250 +  my_main_ptr main;
   1.251 +  int ci;
   1.252 +  jpeg_component_info *compptr;
   1.253 +
   1.254 +  main = (my_main_ptr)
   1.255 +    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
   1.256 +				SIZEOF(my_main_controller));
   1.257 +  cinfo->main = (struct jpeg_c_main_controller *) main;
   1.258 +  main->pub.start_pass = start_pass_main;
   1.259 +
   1.260 +  /* We don't need to create a buffer in raw-data mode. */
   1.261 +  if (cinfo->raw_data_in)
   1.262 +    return;
   1.263 +
   1.264 +  /* Create the buffer.  It holds downsampled data, so each component
   1.265 +   * may be of a different size.
   1.266 +   */
   1.267 +  if (need_full_buffer) {
   1.268 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
   1.269 +    /* Allocate a full-image virtual array for each component */
   1.270 +    /* Note we pad the bottom to a multiple of the iMCU height */
   1.271 +    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
   1.272 +	 ci++, compptr++) {
   1.273 +      main->whole_image[ci] = (*cinfo->mem->request_virt_sarray)
   1.274 +	((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
   1.275 +	 compptr->width_in_blocks * DCTSIZE,
   1.276 +	 (JDIMENSION) jround_up((long) compptr->height_in_blocks,
   1.277 +				(long) compptr->v_samp_factor) * DCTSIZE,
   1.278 +	 (JDIMENSION) (compptr->v_samp_factor * DCTSIZE));
   1.279 +    }
   1.280 +#else
   1.281 +    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
   1.282 +#endif
   1.283 +  } else {
   1.284 +#ifdef FULL_MAIN_BUFFER_SUPPORTED
   1.285 +    main->whole_image[0] = NULL; /* flag for no virtual arrays */
   1.286 +#endif
   1.287 +    /* Allocate a strip buffer for each component */
   1.288 +    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
   1.289 +	 ci++, compptr++) {
   1.290 +      main->buffer[ci] = (*cinfo->mem->alloc_sarray)
   1.291 +	((j_common_ptr) cinfo, JPOOL_IMAGE,
   1.292 +	 compptr->width_in_blocks * DCTSIZE,
   1.293 +	 (JDIMENSION) (compptr->v_samp_factor * DCTSIZE));
   1.294 +    }
   1.295 +  }
   1.296 +}