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modules/javafx.graphics/src/main/native-iio/libjpeg7/jdmainct.c

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@@ -1,9 +1,10 @@
 /*
  * jdmainct.c
  *
  * Copyright (C) 1994-1996, Thomas G. Lane.
+ * Modified 2002-2016 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 the main buffer controller for decompression.
  * The main buffer lies between the JPEG decompressor proper and the

@@ -23,23 +24,23 @@
  * buffer; any full-height buffers will be found inside the coefficient or
  * postprocessing controllers.  Nonetheless, the main controller is not
  * trivial.  Its responsibility is to provide context rows for upsampling/
  * rescaling, and doing this in an efficient fashion is a bit tricky.
  *
- * Postprocessor input data is counted in "row groups".  A row group
- * is defined to be (v_samp_factor * DCT_scaled_size / min_DCT_scaled_size)
+ * Postprocessor input data is counted in "row groups".  A row group is
+ * defined to be (v_samp_factor * DCT_v_scaled_size / min_DCT_v_scaled_size)
  * sample rows of each component.  (We require DCT_scaled_size values to be
  * chosen such that these numbers are integers.  In practice DCT_scaled_size
  * values will likely be powers of two, so we actually have the stronger
  * condition that DCT_scaled_size / min_DCT_scaled_size is an integer.)
  * Upsampling will typically produce max_v_samp_factor pixel rows from each
  * row group (times any additional scale factor that the upsampler is
  * applying).
  *
  * The coefficient controller will deliver data to us one iMCU row at a time;
- * each iMCU row contains v_samp_factor * DCT_scaled_size sample rows, or
- * exactly min_DCT_scaled_size row groups.  (This amount of data corresponds
+ * each iMCU row contains v_samp_factor * DCT_v_scaled_size sample rows, or
+ * exactly min_DCT_v_scaled_size row groups.  (This amount of data corresponds
  * to one row of MCUs when the image is fully interleaved.)  Note that the
  * number of sample rows varies across components, but the number of row
  * groups does not.  Some garbage sample rows may be included in the last iMCU
  * row at the bottom of the image.
  *

@@ -72,11 +73,11 @@
  * can't be processed until we have another row group for its below-context,
  * and so we have to save the next-to-last group too for its above-context.)
  * We could do this most simply by copying data around in our buffer, but
  * that'd be very slow.  We can avoid copying any data by creating a rather
  * strange pointer structure.  Here's how it works.  We allocate a workspace
- * consisting of M+2 row groups (where M = min_DCT_scaled_size is the number
+ * consisting of M+2 row groups (where M = min_DCT_v_scaled_size is the number
  * of row groups per iMCU row).  We create two sets of redundant pointers to
  * the workspace.  Labeling the physical row groups 0 to M+1, the synthesized
  * pointer lists look like this:
  *                   M+1                          M-1
  * master pointer --> 0         master pointer --> 0

@@ -97,15 +98,15 @@
  * The above pictures describe the normal state of the pointer lists.
  * At top and bottom of the image, we diddle the pointer lists to duplicate
  * the first or last sample row as necessary (this is cheaper than copying
  * sample rows around).
  *
- * This scheme breaks down if M < 2, ie, min_DCT_scaled_size is 1.  In that
+ * This scheme breaks down if M < 2, ie, min_DCT_v_scaled_size is 1.  In that
  * situation each iMCU row provides only one row group so the buffering logic
  * must be different (eg, we must read two iMCU rows before we can emit the
  * first row group).  For now, we simply do not support providing context
- * rows when min_DCT_scaled_size is 1.  That combination seems unlikely to
+ * rows when min_DCT_v_scaled_size is 1.  That combination seems unlikely to
  * be worth providing --- if someone wants a 1/8th-size preview, they probably
  * want it quick and dirty, so a context-free upsampler is sufficient.
  */
 
 

@@ -115,21 +116,22 @@
   struct jpeg_d_main_controller pub; /* public fields */
 
   /* Pointer to allocated workspace (M or M+2 row groups). */
   JSAMPARRAY buffer[MAX_COMPONENTS];
 
-  boolean buffer_full;          /* Have we gotten an iMCU row from decoder? */
   JDIMENSION rowgroup_ctr;      /* counts row groups output to postprocessor */
+  JDIMENSION rowgroups_avail;   /* row groups available to postprocessor */
 
   /* Remaining fields are only used in the context case. */
 
+  boolean buffer_full;          /* Have we gotten an iMCU row from decoder? */
+
   /* These are the master pointers to the funny-order pointer lists. */
   JSAMPIMAGE xbuffer[2];        /* pointers to weird pointer lists */
 
   int whichptr;                 /* indicates which pointer set is now in use */
   int context_state;            /* process_data state machine status */
-  JDIMENSION rowgroups_avail;   /* row groups available to postprocessor */
   JDIMENSION iMCU_row_ctr;      /* counts iMCU rows to detect image top/bot */
 } my_main_controller;
 
 typedef my_main_controller * my_main_ptr;
 

@@ -157,23 +159,23 @@
 alloc_funny_pointers (j_decompress_ptr cinfo)
 /* Allocate space for the funny pointer lists.
  * This is done only once, not once per pass.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
   int ci, rgroup;
   int M = cinfo->min_DCT_v_scaled_size;
   jpeg_component_info *compptr;
   JSAMPARRAY xbuf;
 
   /* Get top-level space for component array pointers.
    * We alloc both arrays with one call to save a few cycles.
    */
-  main->xbuffer[0] = (JSAMPIMAGE)
+  mainp->xbuffer[0] = (JSAMPIMAGE)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                 cinfo->num_components * 2 * SIZEOF(JSAMPARRAY));
-  main->xbuffer[1] = main->xbuffer[0] + cinfo->num_components;
+  mainp->xbuffer[1] = mainp->xbuffer[0] + cinfo->num_components;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
       cinfo->min_DCT_v_scaled_size; /* height of a row group of component */

@@ -182,40 +184,40 @@
      */
     xbuf = (JSAMPARRAY)
       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                   2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW));
     xbuf += rgroup;             /* want one row group at negative offsets */
-    main->xbuffer[0][ci] = xbuf;
+    mainp->xbuffer[0][ci] = xbuf;
     xbuf += rgroup * (M + 4);
-    main->xbuffer[1][ci] = xbuf;
+    mainp->xbuffer[1][ci] = xbuf;
   }
 }
 
 
 LOCAL(void)
 make_funny_pointers (j_decompress_ptr cinfo)
 /* Create the funny pointer lists discussed in the comments above.
- * The actual workspace is already allocated (in main->buffer),
+ * The actual workspace is already allocated (in mainp->buffer),
  * and the space for the pointer lists is allocated too.
  * This routine just fills in the curiously ordered lists.
  * This will be repeated at the beginning of each pass.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
   int ci, i, rgroup;
   int M = cinfo->min_DCT_v_scaled_size;
   jpeg_component_info *compptr;
   JSAMPARRAY buf, xbuf0, xbuf1;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
       cinfo->min_DCT_v_scaled_size; /* height of a row group of component */
-    xbuf0 = main->xbuffer[0][ci];
-    xbuf1 = main->xbuffer[1][ci];
+    xbuf0 = mainp->xbuffer[0][ci];
+    xbuf1 = mainp->xbuffer[1][ci];
     /* First copy the workspace pointers as-is */
-    buf = main->buffer[ci];
+    buf = mainp->buffer[ci];
     for (i = 0; i < rgroup * (M + 2); i++) {
       xbuf0[i] = xbuf1[i] = buf[i];
     }
     /* In the second list, put the last four row groups in swapped order */
     for (i = 0; i < rgroup * 2; i++) {

@@ -238,22 +240,22 @@
 set_wraparound_pointers (j_decompress_ptr cinfo)
 /* Set up the "wraparound" pointers at top and bottom of the pointer lists.
  * This changes the pointer list state from top-of-image to the normal state.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
   int ci, i, rgroup;
   int M = cinfo->min_DCT_v_scaled_size;
   jpeg_component_info *compptr;
   JSAMPARRAY xbuf0, xbuf1;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
       cinfo->min_DCT_v_scaled_size; /* height of a row group of component */
-    xbuf0 = main->xbuffer[0][ci];
-    xbuf1 = main->xbuffer[1][ci];
+    xbuf0 = mainp->xbuffer[0][ci];
+    xbuf1 = mainp->xbuffer[1][ci];
     for (i = 0; i < rgroup; i++) {
       xbuf0[i - rgroup] = xbuf0[rgroup*(M+1) + i];
       xbuf1[i - rgroup] = xbuf1[rgroup*(M+1) + i];
       xbuf0[rgroup*(M+2) + i] = xbuf0[i];
       xbuf1[rgroup*(M+2) + i] = xbuf1[i];

@@ -267,11 +269,11 @@
 /* Change the pointer lists to duplicate the last sample row at the bottom
  * of the image.  whichptr indicates which xbuffer holds the final iMCU row.
  * Also sets rowgroups_avail to indicate number of nondummy row groups in row.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
   int ci, i, rgroup, iMCUheight, rows_left;
   jpeg_component_info *compptr;
   JSAMPARRAY xbuf;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

@@ -284,16 +286,16 @@
     if (rows_left == 0) rows_left = iMCUheight;
     /* Count nondummy row groups.  Should get same answer for each component,
      * so we need only do it once.
      */
     if (ci == 0) {
-      main->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1);
+      mainp->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1);
     }
     /* Duplicate the last real sample row rgroup*2 times; this pads out the
      * last partial rowgroup and ensures at least one full rowgroup of context.
      */
-    xbuf = main->xbuffer[main->whichptr][ci];
+    xbuf = mainp->xbuffer[mainp->whichptr][ci];
     for (i = 0; i < rgroup * 2; i++) {
       xbuf[rows_left + i] = xbuf[rows_left-1];
     }
   }
 }

@@ -304,31 +306,31 @@
  */
 
 METHODDEF(void)
 start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
 
   switch (pass_mode) {
   case JBUF_PASS_THRU:
     if (cinfo->upsample->need_context_rows) {
-      main->pub.process_data = process_data_context_main;
+      mainp->pub.process_data = process_data_context_main;
       make_funny_pointers(cinfo); /* Create the xbuffer[] lists */
-      main->whichptr = 0;       /* Read first iMCU row into xbuffer[0] */
-      main->context_state = CTX_PREPARE_FOR_IMCU;
-      main->iMCU_row_ctr = 0;
+      mainp->whichptr = 0;      /* Read first iMCU row into xbuffer[0] */
+      mainp->context_state = CTX_PREPARE_FOR_IMCU;
+      mainp->iMCU_row_ctr = 0;
+      mainp->buffer_full = FALSE; /* Mark buffer empty */
     } else {
       /* Simple case with no context needed */
-      main->pub.process_data = process_data_simple_main;
+      mainp->pub.process_data = process_data_simple_main;
+      mainp->rowgroup_ctr = mainp->rowgroups_avail; /* Mark buffer empty */
     }
-    main->buffer_full = FALSE;  /* Mark buffer empty */
-    main->rowgroup_ctr = 0;
     break;
 #ifdef QUANT_2PASS_SUPPORTED
   case JBUF_CRANK_DEST:
     /* For last pass of 2-pass quantization, just crank the postprocessor */
-    main->pub.process_data = process_data_crank_post;
+    mainp->pub.process_data = process_data_crank_post;
     break;
 #endif
   default:
     ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
     break;

@@ -344,37 +346,28 @@
 METHODDEF(void)
 process_data_simple_main (j_decompress_ptr cinfo,
                           JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
                           JDIMENSION out_rows_avail)
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
-  JDIMENSION rowgroups_avail;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
 
   /* Read input data if we haven't filled the main buffer yet */
-  if (! main->buffer_full) {
-    if (! (*cinfo->coef->decompress_data) (cinfo, main->buffer))
+  if (mainp->rowgroup_ctr >= mainp->rowgroups_avail) {
+    if (! (*cinfo->coef->decompress_data) (cinfo, mainp->buffer))
       return;                   /* suspension forced, can do nothing more */
-    main->buffer_full = TRUE;   /* OK, we have an iMCU row to work with */
+    mainp->rowgroup_ctr = 0;    /* OK, we have an iMCU row to work with */
   }
 
-  /* There are always min_DCT_scaled_size row groups in an iMCU row. */
-  rowgroups_avail = (JDIMENSION) cinfo->min_DCT_v_scaled_size;
   /* Note: at the bottom of the image, we may pass extra garbage row groups
    * to the postprocessor.  The postprocessor has to check for bottom
    * of image anyway (at row resolution), so no point in us doing it too.
    */
 
   /* Feed the postprocessor */
-  (*cinfo->post->post_process_data) (cinfo, main->buffer,
-                                     &main->rowgroup_ctr, rowgroups_avail,
+  (*cinfo->post->post_process_data) (cinfo, mainp->buffer,
+                        &mainp->rowgroup_ctr, mainp->rowgroups_avail,
                                      output_buf, out_row_ctr, out_rows_avail);
-
-  /* Has postprocessor consumed all the data yet? If so, mark buffer empty */
-  if (main->rowgroup_ctr >= rowgroups_avail) {
-    main->buffer_full = FALSE;
-    main->rowgroup_ctr = 0;
-  }
 }
 
 
 /*
  * Process some data.

@@ -384,67 +377,67 @@
 METHODDEF(void)
 process_data_context_main (j_decompress_ptr cinfo,
                            JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
                            JDIMENSION out_rows_avail)
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr mainp = (my_main_ptr) cinfo->main;
 
   /* Read input data if we haven't filled the main buffer yet */
-  if (! main->buffer_full) {
+  if (! mainp->buffer_full) {
     if (! (*cinfo->coef->decompress_data) (cinfo,
-                                           main->xbuffer[main->whichptr]))
+                                           mainp->xbuffer[mainp->whichptr]))
       return;                   /* suspension forced, can do nothing more */
-    main->buffer_full = TRUE;   /* OK, we have an iMCU row to work with */
-    main->iMCU_row_ctr++;       /* count rows received */
+    mainp->buffer_full = TRUE;  /* OK, we have an iMCU row to work with */
+    mainp->iMCU_row_ctr++;      /* count rows received */
   }
 
   /* Postprocessor typically will not swallow all the input data it is handed
    * in one call (due to filling the output buffer first).  Must be prepared
    * to exit and restart.  This switch lets us keep track of how far we got.
    * Note that each case falls through to the next on successful completion.
    */
-  switch (main->context_state) {
+  switch (mainp->context_state) {
   case CTX_POSTPONED_ROW:
     /* Call postprocessor using previously set pointers for postponed row */
-    (*cinfo->post->post_process_data) (cinfo, main->xbuffer[main->whichptr],
-                        &main->rowgroup_ctr, main->rowgroups_avail,
+    (*cinfo->post->post_process_data) (cinfo, mainp->xbuffer[mainp->whichptr],
+                        &mainp->rowgroup_ctr, mainp->rowgroups_avail,
                         output_buf, out_row_ctr, out_rows_avail);
-    if (main->rowgroup_ctr < main->rowgroups_avail)
+    if (mainp->rowgroup_ctr < mainp->rowgroups_avail)
       return;                   /* Need to suspend */
-    main->context_state = CTX_PREPARE_FOR_IMCU;
+    mainp->context_state = CTX_PREPARE_FOR_IMCU;
     if (*out_row_ctr >= out_rows_avail)
       return;                   /* Postprocessor exactly filled output buf */
     /*FALLTHROUGH*/
   case CTX_PREPARE_FOR_IMCU:
     /* Prepare to process first M-1 row groups of this iMCU row */
-    main->rowgroup_ctr = 0;
-    main->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_v_scaled_size - 1);
+    mainp->rowgroup_ctr = 0;
+    mainp->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_v_scaled_size - 1);
     /* Check for bottom of image: if so, tweak pointers to "duplicate"
      * the last sample row, and adjust rowgroups_avail to ignore padding rows.
      */
-    if (main->iMCU_row_ctr == cinfo->total_iMCU_rows)
+    if (mainp->iMCU_row_ctr == cinfo->total_iMCU_rows)
       set_bottom_pointers(cinfo);
-    main->context_state = CTX_PROCESS_IMCU;
+    mainp->context_state = CTX_PROCESS_IMCU;
     /*FALLTHROUGH*/
   case CTX_PROCESS_IMCU:
     /* Call postprocessor using previously set pointers */
-    (*cinfo->post->post_process_data) (cinfo, main->xbuffer[main->whichptr],
-                        &main->rowgroup_ctr, main->rowgroups_avail,
+    (*cinfo->post->post_process_data) (cinfo, mainp->xbuffer[mainp->whichptr],
+                        &mainp->rowgroup_ctr, mainp->rowgroups_avail,
                         output_buf, out_row_ctr, out_rows_avail);
-    if (main->rowgroup_ctr < main->rowgroups_avail)
+    if (mainp->rowgroup_ctr < mainp->rowgroups_avail)
       return;                   /* Need to suspend */
     /* After the first iMCU, change wraparound pointers to normal state */
-    if (main->iMCU_row_ctr == 1)
+    if (mainp->iMCU_row_ctr == 1)
       set_wraparound_pointers(cinfo);
     /* Prepare to load new iMCU row using other xbuffer list */
-    main->whichptr ^= 1;        /* 0=>1 or 1=>0 */
-    main->buffer_full = FALSE;
+    mainp->whichptr ^= 1;       /* 0=>1 or 1=>0 */
+    mainp->buffer_full = FALSE;
     /* Still need to process last row group of this iMCU row, */
     /* which is saved at index M+1 of the other xbuffer */
-    main->rowgroup_ctr = (JDIMENSION) (cinfo->min_DCT_v_scaled_size + 1);
-    main->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_v_scaled_size + 2);
-    main->context_state = CTX_POSTPONED_ROW;
+    mainp->rowgroup_ctr = (JDIMENSION) (cinfo->min_DCT_v_scaled_size + 1);
+    mainp->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_v_scaled_size + 2);
+    mainp->context_state = CTX_POSTPONED_ROW;
   }
 }
 
 
 /*

@@ -473,19 +466,19 @@
  */
 
 GLOBAL(void)
 jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer)
 {
-  my_main_ptr main;
+  my_main_ptr mainp;
   int ci, rgroup, ngroups;
   jpeg_component_info *compptr;
 
-  main = (my_main_ptr)
+  mainp = (my_main_ptr)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                 SIZEOF(my_main_controller));
-  cinfo->main = (struct jpeg_d_main_controller *) main;
-  main->pub.start_pass = start_pass_main;
+  cinfo->main = &mainp->pub;
+  mainp->pub.start_pass = start_pass_main;
 
   if (need_full_buffer)         /* shouldn't happen */
     ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
 
   /* Allocate the workspace.

@@ -495,18 +488,20 @@
     if (cinfo->min_DCT_v_scaled_size < 2) /* unsupported, see comments above */
       ERREXIT(cinfo, JERR_NOTIMPL);
     alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */
     ngroups = cinfo->min_DCT_v_scaled_size + 2;
   } else {
+    /* There are always min_DCT_v_scaled_size row groups in an iMCU row. */
     ngroups = cinfo->min_DCT_v_scaled_size;
+    mainp->rowgroups_avail = (JDIMENSION) ngroups;
   }
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
       cinfo->min_DCT_v_scaled_size; /* height of a row group of component */
-    main->buffer[ci] = (*cinfo->mem->alloc_sarray)
+    mainp->buffer[ci] = (*cinfo->mem->alloc_sarray)
                         ((j_common_ptr) cinfo, JPOOL_IMAGE,
-                         compptr->width_in_blocks * compptr->DCT_h_scaled_size,
+       compptr->width_in_blocks * ((JDIMENSION) compptr->DCT_h_scaled_size),
                          (JDIMENSION) (rgroup * ngroups));
   }
 }
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