1 files changed, 358 insertions, 0 deletions
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jcprepct.c b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jcprepct.c
new file mode 100644
index 0000000..00101e0
--- /dev/null
+++ b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jcprepct.c
@@ -0,0 +1,358 @@
+/*
+ * jcprepct.c
+ *
+ * Copyright (C) 1994-1996, Thomas G. Lane.
+ * 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 compression preprocessing controller.
+ * This controller manages the color conversion, downsampling,
+ * and edge expansion steps.
+ *
+ * Most of the complexity here is associated with buffering input rows
+ * as required by the downsampler.  See the comments at the head of
+ * jcsample.c for the downsampler's needs.
+ */
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+/* At present, jcsample.c can request context rows only for smoothing.
+ * In the future, we might also need context rows for CCIR601 sampling
+ * or other more-complex downsampling procedures.  The code to support
+ * context rows should be compiled only if needed.
+ */
+#ifdef INPUT_SMOOTHING_SUPPORTED
+#define CONTEXT_ROWS_SUPPORTED
+#endif
+/*
+ * For the simple (no-context-row) case, we just need to buffer one
+ * row group's worth of pixels for the downsampling step.  At the bottom of
+ * the image, we pad to a full row group by replicating the last pixel row.
+ * The downsampler's last output row is then replicated if needed to pad
+ * out to a full iMCU row.
+ *
+ * When providing context rows, we must buffer three row groups' worth of
+ * pixels.  Three row groups are physically allocated, but the row pointer
+ * arrays are made five row groups high, with the extra pointers above and
+ * below "wrapping around" to point to the last and first real row groups.
+ * This allows the downsampler to access the proper context rows.
+ * At the top and bottom of the image, we create dummy context rows by
+ * copying the first or last real pixel row.  This copying could be avoided
+ * by pointer hacking as is done in jdmainct.c, but it doesn't seem worth the
+ * trouble on the compression side.
+ */
+/* Private buffer controller object */
+typedef struct {
+  struct jpeg_c_prep_controller pub; /* public fields */
+  /* Downsampling input buffer.  This buffer holds color-converted data
+   * until we have enough to do a downsample step.
+   */
+  JSAMPARRAY color_buf[MAX_COMPONENTS];
+  JDIMENSION rows_to_go;        /* counts rows remaining in source image */
+  int next_buf_row;             /* index of next row to store in color_buf */
+#ifdef CONTEXT_ROWS_SUPPORTED   /* only needed for context case */
+  int this_row_group;           /* starting row index of group to process */
+  int next_buf_stop;            /* downsample when we reach this index */
+#endif
+} my_prep_controller;
+typedef my_prep_controller * my_prep_ptr;
+/*
+ * Initialize for a processing pass.
+ */
+METHODDEF(void)
+start_pass_prep (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
+{
+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
+  if (pass_mode != JBUF_PASS_THRU)
+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
+  /* Initialize total-height counter for detecting bottom of image */
+  prep->rows_to_go = cinfo->image_height;
+  /* Mark the conversion buffer empty */
+  prep->next_buf_row = 0;
+#ifdef CONTEXT_ROWS_SUPPORTED
+  /* Preset additional state variables for context mode.
+   * These aren't used in non-context mode, so we needn't test which mode.
+   */
+  prep->this_row_group = 0;
+  /* Set next_buf_stop to stop after two row groups have been read in. */
+  prep->next_buf_stop = 2 * cinfo->max_v_samp_factor;
+#endif
+}
+/*
+ * Expand an image vertically from height input_rows to height output_rows,
+ * by duplicating the bottom row.
+ */
+LOCAL(void)
+expand_bottom_edge (JSAMPARRAY image_data, JDIMENSION num_cols,
+                    int input_rows, int output_rows)
+{
+  register int row;
+  for (row = input_rows; row < output_rows; row++) {
+    jcopy_sample_rows(image_data, input_rows-1, image_data, row,
+                      1, num_cols);
+  }
+}
+/*
+ * Process some data in the simple no-context case.
+ *
+ * Preprocessor output data is counted in "row groups".  A row group
+ * is defined to be v_samp_factor sample rows of each component.
+ * Downsampling will produce this much data from each max_v_samp_factor
+ * input rows.
+ */
+METHODDEF(void)
+pre_process_data (j_compress_ptr cinfo,
+                  JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
+                  JDIMENSION in_rows_avail,
+                  JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
+                  JDIMENSION out_row_groups_avail)
+{
+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
+  int numrows, ci;
+  JDIMENSION inrows;
+  jpeg_component_info * compptr;
+  while (*in_row_ctr < in_rows_avail &&
+         *out_row_group_ctr < out_row_groups_avail) {
+    /* Do color conversion to fill the conversion buffer. */
+    inrows = in_rows_avail - *in_row_ctr;
+    numrows = cinfo->max_v_samp_factor - prep->next_buf_row;
+    numrows = (int) MIN((JDIMENSION) numrows, inrows);
+    (*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,
+                                       prep->color_buf,
+                                       (JDIMENSION) prep->next_buf_row,
+                                       numrows);
+    *in_row_ctr += numrows;
+    prep->next_buf_row += numrows;
+    prep->rows_to_go -= numrows;
+    /* If at bottom of image, pad to fill the conversion buffer. */
+    if (prep->rows_to_go == 0 &&
+        prep->next_buf_row < cinfo->max_v_samp_factor) {
+      for (ci = 0; ci < cinfo->num_components; ci++) {
+        expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
+                           prep->next_buf_row, cinfo->max_v_samp_factor);
+      }
+      prep->next_buf_row = cinfo->max_v_samp_factor;
+    }
+    /* If we've filled the conversion buffer, empty it. */
+    if (prep->next_buf_row == cinfo->max_v_samp_factor) {
+      (*cinfo->downsample->downsample) (cinfo,
+                                        prep->color_buf, (JDIMENSION) 0,
+                                        output_buf, *out_row_group_ctr);
+      prep->next_buf_row = 0;
+      (*out_row_group_ctr)++;
+    }
+    /* If at bottom of image, pad the output to a full iMCU height.
+     * Note we assume the caller is providing a one-iMCU-height output buffer!
+     */
+    if (prep->rows_to_go == 0 &&
+        *out_row_group_ctr < out_row_groups_avail) {
+      for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+           ci++, compptr++) {
+        numrows = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
+                  cinfo->min_DCT_v_scaled_size;
+        expand_bottom_edge(output_buf[ci],
+                           compptr->width_in_blocks * compptr->DCT_h_scaled_size,
+                           (int) (*out_row_group_ctr * numrows),
+                           (int) (out_row_groups_avail * numrows));
+      }
+      *out_row_group_ctr = out_row_groups_avail;
+      break;                    /* can exit outer loop without test */
+    }
+  }
+}
+#ifdef CONTEXT_ROWS_SUPPORTED
+/*
+ * Process some data in the context case.
+ */
+METHODDEF(void)
+pre_process_context (j_compress_ptr cinfo,
+                     JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
+                     JDIMENSION in_rows_avail,
+                     JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
+                     JDIMENSION out_row_groups_avail)
+{
+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
+  int numrows, ci;
+  int buf_height = cinfo->max_v_samp_factor * 3;
+  JDIMENSION inrows;
+  while (*out_row_group_ctr < out_row_groups_avail) {
+    if (*in_row_ctr < in_rows_avail) {
+      /* Do color conversion to fill the conversion buffer. */
+      inrows = in_rows_avail - *in_row_ctr;
+      numrows = prep->next_buf_stop - prep->next_buf_row;
+      numrows = (int) MIN((JDIMENSION) numrows, inrows);
+      (*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,
+                                         prep->color_buf,
+                                         (JDIMENSION) prep->next_buf_row,
+                                         numrows);
+      /* Pad at top of image, if first time through */
+      if (prep->rows_to_go == cinfo->image_height) {
+        for (ci = 0; ci < cinfo->num_components; ci++) {
+          int row;
+          for (row = 1; row <= cinfo->max_v_samp_factor; row++) {
+            jcopy_sample_rows(prep->color_buf[ci], 0,
+                              prep->color_buf[ci], -row,
+                              1, cinfo->image_width);
+          }
+        }
+      }
+      *in_row_ctr += numrows;
+      prep->next_buf_row += numrows;
+      prep->rows_to_go -= numrows;
+    } else {
+      /* Return for more data, unless we are at the bottom of the image. */
+      if (prep->rows_to_go != 0)
+        break;
+      /* When at bottom of image, pad to fill the conversion buffer. */
+      if (prep->next_buf_row < prep->next_buf_stop) {
+        for (ci = 0; ci < cinfo->num_components; ci++) {
+          expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
+                             prep->next_buf_row, prep->next_buf_stop);
+        }
+        prep->next_buf_row = prep->next_buf_stop;
+      }
+    }
+    /* If we've gotten enough data, downsample a row group. */
+    if (prep->next_buf_row == prep->next_buf_stop) {
+      (*cinfo->downsample->downsample) (cinfo,
+                                        prep->color_buf,
+                                        (JDIMENSION) prep->this_row_group,
+                                        output_buf, *out_row_group_ctr);
+      (*out_row_group_ctr)++;
+      /* Advance pointers with wraparound as necessary. */
+      prep->this_row_group += cinfo->max_v_samp_factor;
+      if (prep->this_row_group >= buf_height)
+        prep->this_row_group = 0;
+      if (prep->next_buf_row >= buf_height)
+        prep->next_buf_row = 0;
+      prep->next_buf_stop = prep->next_buf_row + cinfo->max_v_samp_factor;
+    }
+  }
+}
+/*
+ * Create the wrapped-around downsampling input buffer needed for context mode.
+ */
+LOCAL(void)
+create_context_buffer (j_compress_ptr cinfo)
+{
+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
+  int rgroup_height = cinfo->max_v_samp_factor;
+  int ci, i;
+  jpeg_component_info * compptr;
+  JSAMPARRAY true_buffer, fake_buffer;
+  /* Grab enough space for fake row pointers for all the components;
+   * we need five row groups' worth of pointers for each component.
+   */
+  fake_buffer = (JSAMPARRAY)
+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+                                (cinfo->num_components * 5 * rgroup_height) *
+                                SIZEOF(JSAMPROW));
+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+       ci++, compptr++) {
+    /* Allocate the actual buffer space (3 row groups) for this component.
+     * We make the buffer wide enough to allow the downsampler to edge-expand
+     * horizontally within the buffer, if it so chooses.
+     */
+    true_buffer = (*cinfo->mem->alloc_sarray)
+      ((j_common_ptr) cinfo, JPOOL_IMAGE,
+       (JDIMENSION) (((long) compptr->width_in_blocks *
+                      cinfo->min_DCT_h_scaled_size *
+                      cinfo->max_h_samp_factor) / compptr->h_samp_factor),
+       (JDIMENSION) (3 * rgroup_height));
+    /* Copy true buffer row pointers into the middle of the fake row array */
+    MEMCOPY(fake_buffer + rgroup_height, true_buffer,
+            3 * rgroup_height * SIZEOF(JSAMPROW));
+    /* Fill in the above and below wraparound pointers */
+    for (i = 0; i < rgroup_height; i++) {
+      fake_buffer[i] = true_buffer[2 * rgroup_height + i];
+      fake_buffer[4 * rgroup_height + i] = true_buffer[i];
+    }
+    prep->color_buf[ci] = fake_buffer + rgroup_height;
+    fake_buffer += 5 * rgroup_height; /* point to space for next component */
+  }
+}
+#endif /* CONTEXT_ROWS_SUPPORTED */
+/*
+ * Initialize preprocessing controller.
+ */
+GLOBAL(void)
+jinit_c_prep_controller (j_compress_ptr cinfo, boolean need_full_buffer)
+{
+  my_prep_ptr prep;
+  int ci;
+  jpeg_component_info * compptr;
+  if (need_full_buffer)         /* safety check */
+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
+  prep = (my_prep_ptr)
+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+                                SIZEOF(my_prep_controller));
+  cinfo->prep = (struct jpeg_c_prep_controller *) prep;
+  prep->pub.start_pass = start_pass_prep;
+  /* Allocate the color conversion buffer.
+   * We make the buffer wide enough to allow the downsampler to edge-expand
+   * horizontally within the buffer, if it so chooses.
+   */
+  if (cinfo->downsample->need_context_rows) {
+    /* Set up to provide context rows */
+#ifdef CONTEXT_ROWS_SUPPORTED
+    prep->pub.pre_process_data = pre_process_context;
+    create_context_buffer(cinfo);
+#else
+    ERREXIT(cinfo, JERR_NOT_COMPILED);
+#endif
+  } else {
+    /* No context, just make it tall enough for one row group */
+    prep->pub.pre_process_data = pre_process_data;
+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+         ci++, compptr++) {
+      prep->color_buf[ci] = (*cinfo->mem->alloc_sarray)
+        ((j_common_ptr) cinfo, JPOOL_IMAGE,
+         (JDIMENSION) (((long) compptr->width_in_blocks *
+                        cinfo->min_DCT_h_scaled_size *
+                        cinfo->max_h_samp_factor) / compptr->h_samp_factor),
+         (JDIMENSION) cinfo->max_v_samp_factor);
+    }
+  }
+}

diff --git a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jcprepct.c b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jcprepct.c new file mode 100644 index 0000000..00101e0 --- /dev/null +++ b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jcprepct.c
@@ -0,0 +1,358 @@
	1	/*
	2	* jcprepct.c
	3	*
	4	* Copyright (C) 1994-1996, Thomas G. Lane.
	5	* This file is part of the Independent JPEG Group's software.
	6	* For conditions of distribution and use, see the accompanying README file.
	7	*
	8	* This file contains the compression preprocessing controller.
	9	* This controller manages the color conversion, downsampling,
	10	* and edge expansion steps.
	11	*
	12	* Most of the complexity here is associated with buffering input rows
	13	* as required by the downsampler. See the comments at the head of
	14	* jcsample.c for the downsampler's needs.
	15	*/
	16
	17	#define JPEG_INTERNALS
	18	#include "jinclude.h"
	19	#include "jpeglib.h"
	20
	21
	22	/* At present, jcsample.c can request context rows only for smoothing.
	23	* In the future, we might also need context rows for CCIR601 sampling
	24	* or other more-complex downsampling procedures. The code to support
	25	* context rows should be compiled only if needed.
	26	*/
	27	#ifdef INPUT_SMOOTHING_SUPPORTED
	28	#define CONTEXT_ROWS_SUPPORTED
	29	#endif
	30
	31
	32	/*
	33	* For the simple (no-context-row) case, we just need to buffer one
	34	* row group's worth of pixels for the downsampling step. At the bottom of
	35	* the image, we pad to a full row group by replicating the last pixel row.
	36	* The downsampler's last output row is then replicated if needed to pad
	37	* out to a full iMCU row.
	38	*
	39	* When providing context rows, we must buffer three row groups' worth of
	40	* pixels. Three row groups are physically allocated, but the row pointer
	41	* arrays are made five row groups high, with the extra pointers above and
	42	* below "wrapping around" to point to the last and first real row groups.
	43	* This allows the downsampler to access the proper context rows.
	44	* At the top and bottom of the image, we create dummy context rows by
	45	* copying the first or last real pixel row. This copying could be avoided
	46	* by pointer hacking as is done in jdmainct.c, but it doesn't seem worth the
	47	* trouble on the compression side.
	48	*/
	49
	50
	51	/* Private buffer controller object */
	52
	53	typedef struct {
	54	struct jpeg_c_prep_controller pub; /* public fields */
	55
	56	/* Downsampling input buffer. This buffer holds color-converted data
	57	* until we have enough to do a downsample step.
	58	*/
	59	JSAMPARRAY color_buf[MAX_COMPONENTS];
	60
	61	JDIMENSION rows_to_go; /* counts rows remaining in source image */
	62	int next_buf_row; /* index of next row to store in color_buf */
	63
	64	#ifdef CONTEXT_ROWS_SUPPORTED /* only needed for context case */
	65	int this_row_group; /* starting row index of group to process */
	66	int next_buf_stop; /* downsample when we reach this index */
	67	#endif
	68	} my_prep_controller;
	69
	70	typedef my_prep_controller * my_prep_ptr;
	71
	72
	73	/*
	74	* Initialize for a processing pass.
	75	*/
	76
	77	METHODDEF(void)
	78	start_pass_prep (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
	79	{
	80	my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
	81
	82	if (pass_mode != JBUF_PASS_THRU)
	83	ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
	84
	85	/* Initialize total-height counter for detecting bottom of image */
	86	prep->rows_to_go = cinfo->image_height;
	87	/* Mark the conversion buffer empty */
	88	prep->next_buf_row = 0;
	89	#ifdef CONTEXT_ROWS_SUPPORTED
	90	/* Preset additional state variables for context mode.
	91	* These aren't used in non-context mode, so we needn't test which mode.
	92	*/
	93	prep->this_row_group = 0;
	94	/* Set next_buf_stop to stop after two row groups have been read in. */
	95	prep->next_buf_stop = 2 * cinfo->max_v_samp_factor;
	96	#endif
	97	}
	98
	99
	100	/*
	101	* Expand an image vertically from height input_rows to height output_rows,
	102	* by duplicating the bottom row.
	103	*/
	104
	105	LOCAL(void)
	106	expand_bottom_edge (JSAMPARRAY image_data, JDIMENSION num_cols,
	107	int input_rows, int output_rows)
	108	{
	109	register int row;
	110
	111	for (row = input_rows; row < output_rows; row++) {
	112	jcopy_sample_rows(image_data, input_rows-1, image_data, row,
	113	1, num_cols);
	114	}
	115	}
	116
	117
	118	/*
	119	* Process some data in the simple no-context case.
	120	*
	121	* Preprocessor output data is counted in "row groups". A row group
	122	* is defined to be v_samp_factor sample rows of each component.
	123	* Downsampling will produce this much data from each max_v_samp_factor
	124	* input rows.
	125	*/
	126
	127	METHODDEF(void)
	128	pre_process_data (j_compress_ptr cinfo,
	129	JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
	130	JDIMENSION in_rows_avail,
	131	JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
	132	JDIMENSION out_row_groups_avail)
	133	{
	134	my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
	135	int numrows, ci;
	136	JDIMENSION inrows;
	137	jpeg_component_info * compptr;
	138
	139	while (*in_row_ctr < in_rows_avail &&
	140	*out_row_group_ctr < out_row_groups_avail) {
	141	/* Do color conversion to fill the conversion buffer. */
	142	inrows = in_rows_avail - *in_row_ctr;
	143	numrows = cinfo->max_v_samp_factor - prep->next_buf_row;
	144	numrows = (int) MIN((JDIMENSION) numrows, inrows);
	145	(cinfo->cconvert->color_convert) (cinfo, input_buf + in_row_ctr,
	146	prep->color_buf,
	147	(JDIMENSION) prep->next_buf_row,
	148	numrows);
	149	*in_row_ctr += numrows;
	150	prep->next_buf_row += numrows;
	151	prep->rows_to_go -= numrows;
	152	/* If at bottom of image, pad to fill the conversion buffer. */
	153	if (prep->rows_to_go == 0 &&
	154	prep->next_buf_row < cinfo->max_v_samp_factor) {
	155	for (ci = 0; ci < cinfo->num_components; ci++) {
	156	expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
	157	prep->next_buf_row, cinfo->max_v_samp_factor);
	158	}
	159	prep->next_buf_row = cinfo->max_v_samp_factor;
	160	}
	161	/* If we've filled the conversion buffer, empty it. */
	162	if (prep->next_buf_row == cinfo->max_v_samp_factor) {
	163	(*cinfo->downsample->downsample) (cinfo,
	164	prep->color_buf, (JDIMENSION) 0,
	165	output_buf, *out_row_group_ctr);
	166	prep->next_buf_row = 0;
	167	(*out_row_group_ctr)++;
	168	}
	169	/* If at bottom of image, pad the output to a full iMCU height.
	170	* Note we assume the caller is providing a one-iMCU-height output buffer!
	171	*/
	172	if (prep->rows_to_go == 0 &&
	173	*out_row_group_ctr < out_row_groups_avail) {
	174	for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
	175	ci++, compptr++) {
	176	numrows = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
	177	cinfo->min_DCT_v_scaled_size;
	178	expand_bottom_edge(output_buf[ci],
	179	compptr->width_in_blocks * compptr->DCT_h_scaled_size,
	180	(int) (out_row_group_ctr numrows),
	181	(int) (out_row_groups_avail * numrows));
	182	}
	183	*out_row_group_ctr = out_row_groups_avail;
	184	break; /* can exit outer loop without test */
	185	}
	186	}
	187	}
	188
	189
	190	#ifdef CONTEXT_ROWS_SUPPORTED
	191
	192	/*
	193	* Process some data in the context case.
	194	*/
	195
	196	METHODDEF(void)
	197	pre_process_context (j_compress_ptr cinfo,
	198	JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
	199	JDIMENSION in_rows_avail,
	200	JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
	201	JDIMENSION out_row_groups_avail)
	202	{
	203	my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
	204	int numrows, ci;
	205	int buf_height = cinfo->max_v_samp_factor * 3;
	206	JDIMENSION inrows;
	207
	208	while (*out_row_group_ctr < out_row_groups_avail) {
	209	if (*in_row_ctr < in_rows_avail) {
	210	/* Do color conversion to fill the conversion buffer. */
	211	inrows = in_rows_avail - *in_row_ctr;
	212	numrows = prep->next_buf_stop - prep->next_buf_row;
	213	numrows = (int) MIN((JDIMENSION) numrows, inrows);
	214	(cinfo->cconvert->color_convert) (cinfo, input_buf + in_row_ctr,
	215	prep->color_buf,
	216	(JDIMENSION) prep->next_buf_row,
	217	numrows);
	218	/* Pad at top of image, if first time through */
	219	if (prep->rows_to_go == cinfo->image_height) {
	220	for (ci = 0; ci < cinfo->num_components; ci++) {
	221	int row;
	222	for (row = 1; row <= cinfo->max_v_samp_factor; row++) {
	223	jcopy_sample_rows(prep->color_buf[ci], 0,
	224	prep->color_buf[ci], -row,
	225	1, cinfo->image_width);
	226	}
	227	}
	228	}
	229	*in_row_ctr += numrows;
	230	prep->next_buf_row += numrows;
	231	prep->rows_to_go -= numrows;
	232	} else {
	233	/* Return for more data, unless we are at the bottom of the image. */
	234	if (prep->rows_to_go != 0)
	235	break;
	236	/* When at bottom of image, pad to fill the conversion buffer. */
	237	if (prep->next_buf_row < prep->next_buf_stop) {
	238	for (ci = 0; ci < cinfo->num_components; ci++) {
	239	expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
	240	prep->next_buf_row, prep->next_buf_stop);
	241	}
	242	prep->next_buf_row = prep->next_buf_stop;
	243	}
	244	}
	245	/* If we've gotten enough data, downsample a row group. */
	246	if (prep->next_buf_row == prep->next_buf_stop) {
	247	(*cinfo->downsample->downsample) (cinfo,
	248	prep->color_buf,
	249	(JDIMENSION) prep->this_row_group,
	250	output_buf, *out_row_group_ctr);
	251	(*out_row_group_ctr)++;
	252	/* Advance pointers with wraparound as necessary. */
	253	prep->this_row_group += cinfo->max_v_samp_factor;
	254	if (prep->this_row_group >= buf_height)
	255	prep->this_row_group = 0;
	256	if (prep->next_buf_row >= buf_height)
	257	prep->next_buf_row = 0;
	258	prep->next_buf_stop = prep->next_buf_row + cinfo->max_v_samp_factor;
	259	}
	260	}
	261	}
	262
	263
	264	/*
	265	* Create the wrapped-around downsampling input buffer needed for context mode.
	266	*/
	267
	268	LOCAL(void)
	269	create_context_buffer (j_compress_ptr cinfo)
	270	{
	271	my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
	272	int rgroup_height = cinfo->max_v_samp_factor;
	273	int ci, i;
	274	jpeg_component_info * compptr;
	275	JSAMPARRAY true_buffer, fake_buffer;
	276
	277	/* Grab enough space for fake row pointers for all the components;
	278	* we need five row groups' worth of pointers for each component.
	279	*/
	280	fake_buffer = (JSAMPARRAY)
	281	(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
	282	(cinfo->num_components * 5 * rgroup_height) *
	283	SIZEOF(JSAMPROW));
	284
	285	for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
	286	ci++, compptr++) {
	287	/* Allocate the actual buffer space (3 row groups) for this component.
	288	* We make the buffer wide enough to allow the downsampler to edge-expand
	289	* horizontally within the buffer, if it so chooses.
	290	*/
	291	true_buffer = (*cinfo->mem->alloc_sarray)
	292	((j_common_ptr) cinfo, JPOOL_IMAGE,
	293	(JDIMENSION) (((long) compptr->width_in_blocks *
	294	cinfo->min_DCT_h_scaled_size *
	295	cinfo->max_h_samp_factor) / compptr->h_samp_factor),
	296	(JDIMENSION) (3 * rgroup_height));
	297	/* Copy true buffer row pointers into the middle of the fake row array */
	298	MEMCOPY(fake_buffer + rgroup_height, true_buffer,
	299	3 * rgroup_height * SIZEOF(JSAMPROW));
	300	/* Fill in the above and below wraparound pointers */
	301	for (i = 0; i < rgroup_height; i++) {
	302	fake_buffer[i] = true_buffer[2 * rgroup_height + i];
	303	fake_buffer[4 * rgroup_height + i] = true_buffer[i];
	304	}
	305	prep->color_buf[ci] = fake_buffer + rgroup_height;
	306	fake_buffer += 5 * rgroup_height; /* point to space for next component */
	307	}
	308	}
	309
	310	#endif /* CONTEXT_ROWS_SUPPORTED */
	311
	312
	313	/*
	314	* Initialize preprocessing controller.
	315	*/
	316
	317	GLOBAL(void)
	318	jinit_c_prep_controller (j_compress_ptr cinfo, boolean need_full_buffer)
	319	{
	320	my_prep_ptr prep;
	321	int ci;
	322	jpeg_component_info * compptr;
	323
	324	if (need_full_buffer) /* safety check */
	325	ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
	326
	327	prep = (my_prep_ptr)
	328	(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
	329	SIZEOF(my_prep_controller));
	330	cinfo->prep = (struct jpeg_c_prep_controller *) prep;
	331	prep->pub.start_pass = start_pass_prep;
	332
	333	/* Allocate the color conversion buffer.
	334	* We make the buffer wide enough to allow the downsampler to edge-expand
	335	* horizontally within the buffer, if it so chooses.
	336	*/
	337	if (cinfo->downsample->need_context_rows) {
	338	/* Set up to provide context rows */
	339	#ifdef CONTEXT_ROWS_SUPPORTED
	340	prep->pub.pre_process_data = pre_process_context;
	341	create_context_buffer(cinfo);
	342	#else
	343	ERREXIT(cinfo, JERR_NOT_COMPILED);
	344	#endif
	345	} else {
	346	/* No context, just make it tall enough for one row group */
	347	prep->pub.pre_process_data = pre_process_data;
	348	for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
	349	ci++, compptr++) {
	350	prep->color_buf[ci] = (*cinfo->mem->alloc_sarray)
	351	((j_common_ptr) cinfo, JPOOL_IMAGE,
	352	(JDIMENSION) (((long) compptr->width_in_blocks *
	353	cinfo->min_DCT_h_scaled_size *
	354	cinfo->max_h_samp_factor) / compptr->h_samp_factor),
	355	(JDIMENSION) cinfo->max_v_samp_factor);
	356	}
	357	}
	358	}