-/*\r
-Copyright (c) 2001, Loki software, inc.\r
-All rights reserved.\r
-\r
-Redistribution and use in source and binary forms, with or without modification, \r
-are permitted provided that the following conditions are met:\r
-\r
-Redistributions of source code must retain the above copyright notice, this list \r
-of conditions and the following disclaimer.\r
-\r
-Redistributions in binary form must reproduce the above copyright notice, this\r
-list of conditions and the following disclaimer in the documentation and/or\r
-other materials provided with the distribution.\r
-\r
-Neither the name of Loki software nor the names of its contributors may be used \r
-to endorse or promote products derived from this software without specific prior \r
-written permission. \r
-\r
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' \r
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE \r
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE \r
-DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY \r
-DIRECT,INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES \r
-(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; \r
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON \r
-ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT \r
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS \r
-SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. \r
-*/\r
-\r
-//\r
-// Functions to load JPEG files from a buffer, based on jdatasrc.c\r
-//\r
-// Leonardo Zide (leo@lokigames.com)\r
-//\r
-\r
-#include <setjmp.h>\r
-#include <stdlib.h>\r
-#include <stdio.h>\r
-#include <string.h>\r
-#include <glib.h>\r
-\r
-extern "C" {\r
-#include "radiant_jpeglib.h"\r
-#include "jpeg6/jerror.h"\r
-}\r
-\r
-#include "image.h"\r
-\r
-/* Expanded data source object for stdio input */\r
-\r
-typedef struct {\r
- struct jpeg_source_mgr pub; /* public fields */\r
-\r
- int src_size;\r
- JOCTET * src_buffer;\r
-\r
- JOCTET * buffer; /* start of buffer */\r
- boolean start_of_file; /* have we gotten any data yet? */\r
-} my_source_mgr;\r
-\r
-typedef my_source_mgr * my_src_ptr;\r
-\r
-#define INPUT_BUF_SIZE 4096 /* choose an efficiently fread'able size */\r
-\r
-\r
-/*\r
- * Initialize source --- called by jpeg_read_header\r
- * before any data is actually read.\r
- */\r
-\r
-static void my_init_source (j_decompress_ptr cinfo)\r
-{\r
- my_src_ptr src = (my_src_ptr) cinfo->src;\r
-\r
- /* We reset the empty-input-file flag for each image,\r
- * but we don't clear the input buffer.\r
- * This is correct behavior for reading a series of images from one source.\r
- */\r
- src->start_of_file = TRUE;\r
-}\r
-\r
-\r
-/*\r
- * Fill the input buffer --- called whenever buffer is emptied.\r
- *\r
- * In typical applications, this should read fresh data into the buffer\r
- * (ignoring the current state of next_input_byte & bytes_in_buffer),\r
- * reset the pointer & count to the start of the buffer, and return TRUE\r
- * indicating that the buffer has been reloaded. It is not necessary to\r
- * fill the buffer entirely, only to obtain at least one more byte.\r
- *\r
- * There is no such thing as an EOF return. If the end of the file has been\r
- * reached, the routine has a choice of ERREXIT() or inserting fake data into\r
- * the buffer. In most cases, generating a warning message and inserting a\r
- * fake EOI marker is the best course of action --- this will allow the\r
- * decompressor to output however much of the image is there. However,\r
- * the resulting error message is misleading if the real problem is an empty\r
- * input file, so we handle that case specially.\r
- *\r
- * In applications that need to be able to suspend compression due to input\r
- * not being available yet, a FALSE return indicates that no more data can be\r
- * obtained right now, but more may be forthcoming later. In this situation,\r
- * the decompressor will return to its caller (with an indication of the\r
- * number of scanlines it has read, if any). The application should resume\r
- * decompression after it has loaded more data into the input buffer. Note\r
- * that there are substantial restrictions on the use of suspension --- see\r
- * the documentation.\r
- *\r
- * When suspending, the decompressor will back up to a convenient restart point\r
- * (typically the start of the current MCU). next_input_byte & bytes_in_buffer\r
- * indicate where the restart point will be if the current call returns FALSE.\r
- * Data beyond this point must be rescanned after resumption, so move it to\r
- * the front of the buffer rather than discarding it.\r
- */\r
-\r
-static boolean my_fill_input_buffer (j_decompress_ptr cinfo)\r
-{\r
- my_src_ptr src = (my_src_ptr) cinfo->src;\r
- size_t nbytes;\r
-\r
- if (src->src_size > INPUT_BUF_SIZE)\r
- nbytes = INPUT_BUF_SIZE;\r
- else\r
- nbytes = src->src_size;\r
-\r
- memcpy (src->buffer, src->src_buffer, nbytes);\r
- src->src_buffer += nbytes;\r
- src->src_size -= nbytes;\r
-\r
- if (nbytes <= 0) {\r
- if (src->start_of_file) /* Treat empty input file as fatal error */\r
- ERREXIT(cinfo, JERR_INPUT_EMPTY);\r
- WARNMS(cinfo, JWRN_JPEG_EOF);\r
- /* Insert a fake EOI marker */\r
- src->buffer[0] = (JOCTET) 0xFF;\r
- src->buffer[1] = (JOCTET) JPEG_EOI;\r
- nbytes = 2;\r
- }\r
-\r
- src->pub.next_input_byte = src->buffer;\r
- src->pub.bytes_in_buffer = nbytes;\r
- src->start_of_file = FALSE;\r
-\r
- return TRUE;\r
-}\r
-\r
-\r
-/*\r
- * Skip data --- used to skip over a potentially large amount of\r
- * uninteresting data (such as an APPn marker).\r
- *\r
- * Writers of suspendable-input applications must note that skip_input_data\r
- * is not granted the right to give a suspension return. If the skip extends\r
- * beyond the data currently in the buffer, the buffer can be marked empty so\r
- * that the next read will cause a fill_input_buffer call that can suspend.\r
- * Arranging for additional bytes to be discarded before reloading the input\r
- * buffer is the application writer's problem.\r
- */\r
-\r
-static void my_skip_input_data (j_decompress_ptr cinfo, long num_bytes)\r
-{\r
- my_src_ptr src = (my_src_ptr) cinfo->src;\r
-\r
- /* Just a dumb implementation for now. Could use fseek() except\r
- * it doesn't work on pipes. Not clear that being smart is worth\r
- * any trouble anyway --- large skips are infrequent.\r
- */\r
- if (num_bytes > 0) {\r
- while (num_bytes > (long) src->pub.bytes_in_buffer) {\r
- num_bytes -= (long) src->pub.bytes_in_buffer;\r
- (void) my_fill_input_buffer(cinfo);\r
- /* note we assume that fill_input_buffer will never return FALSE,\r
- * so suspension need not be handled.\r
- */\r
- }\r
- src->pub.next_input_byte += (size_t) num_bytes;\r
- src->pub.bytes_in_buffer -= (size_t) num_bytes;\r
- }\r
-}\r
-\r
-\r
-/*\r
- * An additional method that can be provided by data source modules is the\r
- * resync_to_restart method for error recovery in the presence of RST markers.\r
- * For the moment, this source module just uses the default resync method\r
- * provided by the JPEG library. That method assumes that no backtracking\r
- * is possible.\r
- */\r
-\r
-\r
-/*\r
- * Terminate source --- called by jpeg_finish_decompress\r
- * after all data has been read. Often a no-op.\r
- *\r
- * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding\r
- * application must deal with any cleanup that should happen even\r
- * for error exit.\r
- */\r
-\r
-static void my_term_source (j_decompress_ptr cinfo)\r
-{\r
- /* no work necessary here */\r
-}\r
-\r
-\r
-/*\r
- * Prepare for input from a stdio stream.\r
- * The caller must have already opened the stream, and is responsible\r
- * for closing it after finishing decompression.\r
- */\r
-\r
-static void jpeg_buffer_src (j_decompress_ptr cinfo, void* buffer, int bufsize)\r
-{\r
- my_src_ptr src;\r
-\r
- /* The source object and input buffer are made permanent so that a series\r
- * of JPEG images can be read from the same file by calling jpeg_stdio_src\r
- * only before the first one. (If we discarded the buffer at the end of\r
- * one image, we'd likely lose the start of the next one.)\r
- * This makes it unsafe to use this manager and a different source\r
- * manager serially with the same JPEG object. Caveat programmer.\r
- */\r
- if (cinfo->src == NULL) { /* first time for this JPEG object? */\r
- cinfo->src = (struct jpeg_source_mgr *)\r
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,\r
- sizeof (my_source_mgr));\r
- src = (my_src_ptr) cinfo->src;\r
- src->buffer = (JOCTET *)\r
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,\r
- INPUT_BUF_SIZE * sizeof (JOCTET));\r
- }\r
-\r
- src = (my_src_ptr) cinfo->src;\r
- src->pub.init_source = my_init_source;\r
- src->pub.fill_input_buffer = my_fill_input_buffer;\r
- src->pub.skip_input_data = my_skip_input_data;\r
- src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */\r
- src->pub.term_source = my_term_source;\r
- src->src_buffer = (JOCTET *)buffer;\r
- src->src_size = bufsize;\r
- src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */\r
- src->pub.next_input_byte = NULL; /* until buffer loaded */\r
-}\r
-\r
-// =============================================================================\r
-\r
-static char errormsg[JMSG_LENGTH_MAX];\r
-\r
-typedef struct my_jpeg_error_mgr\r
-{\r
- struct jpeg_error_mgr pub; // "public" fields\r
- jmp_buf setjmp_buffer; // for return to caller \r
-} bt_jpeg_error_mgr;\r
-\r
-static void my_jpeg_error_exit (j_common_ptr cinfo)\r
-{\r
- my_jpeg_error_mgr* myerr = (bt_jpeg_error_mgr*) cinfo->err;\r
-\r
- (*cinfo->err->format_message) (cinfo, errormsg);\r
-\r
- longjmp (myerr->setjmp_buffer, 1);\r
-}\r
-\r
-// stash a scanline\r
-static void j_putRGBScanline (unsigned char* jpegline, int widthPix, unsigned char* outBuf, int row)\r
-{\r
- int offset = row * widthPix * 4;\r
- int count;\r
-\r
- for (count = 0; count < widthPix; count++) \r
- {\r
- unsigned char iRed, iBlu, iGrn;\r
- unsigned char *oRed, *oBlu, *oGrn, *oAlp;\r
-\r
- iRed = *(jpegline + count * 3 + 0);\r
- iGrn = *(jpegline + count * 3 + 1);\r
- iBlu = *(jpegline + count * 3 + 2);\r
-\r
- oRed = outBuf + offset + count * 4 + 0;\r
- oGrn = outBuf + offset + count * 4 + 1;\r
- oBlu = outBuf + offset + count * 4 + 2;\r
- oAlp = outBuf + offset + count * 4 + 3;\r
-\r
- *oRed = iRed;\r
- *oGrn = iGrn;\r
- *oBlu = iBlu;\r
- *oAlp = 255;\r
- }\r
-}\r
-\r
-// stash a scanline\r
-static void j_putRGBAScanline (unsigned char* jpegline, int widthPix, unsigned char* outBuf, int row)\r
-{\r
- int offset = row * widthPix * 4;\r
- int count;\r
-\r
- for (count = 0; count < widthPix; count++) \r
- {\r
- unsigned char iRed, iBlu, iGrn, iAlp;\r
- unsigned char *oRed, *oBlu, *oGrn, *oAlp;\r
-\r
- iRed = *(jpegline + count * 4 + 0);\r
- iGrn = *(jpegline + count * 4 + 1);\r
- iBlu = *(jpegline + count * 4 + 2);\r
- iAlp = *(jpegline + count * 4 + 3);\r
-\r
- oRed = outBuf + offset + count * 4 + 0;\r
- oGrn = outBuf + offset + count * 4 + 1;\r
- oBlu = outBuf + offset + count * 4 + 2;\r
- oAlp = outBuf + offset + count * 4 + 3;\r
-\r
- *oRed = iRed;\r
- *oGrn = iGrn;\r
- *oBlu = iBlu;\r
- // ydnar: see bug 900\r
- *oAlp = 255; //% iAlp;\r
- }\r
-}\r
-\r
-// stash a gray scanline\r
-static void j_putGrayScanlineToRGB (unsigned char* jpegline, int widthPix, unsigned char* outBuf, int row)\r
-{\r
- int offset = row * widthPix * 4;\r
- int count;\r
-\r
- for (count = 0; count < widthPix; count++) \r
- {\r
- unsigned char iGray;\r
- unsigned char *oRed, *oBlu, *oGrn, *oAlp;\r
-\r
- // get our grayscale value\r
- iGray = *(jpegline + count);\r
-\r
- oRed = outBuf + offset + count * 4;\r
- oGrn = outBuf + offset + count * 4 + 1;\r
- oBlu = outBuf + offset + count * 4 + 2;\r
- oAlp = outBuf + offset + count * 4 + 3;\r
-\r
- *oRed = iGray;\r
- *oGrn = iGray;\r
- *oBlu = iGray;\r
- *oAlp = 255;\r
- }\r
-}\r
-\r
-static int _LoadJPGBuff (void *src_buffer, int src_size, unsigned char **pic, int *width, int *height) \r
-{\r
- struct jpeg_decompress_struct cinfo;\r
- struct my_jpeg_error_mgr jerr;\r
- JSAMPARRAY buffer;\r
- int row_stride, size;\r
-\r
- cinfo.err = jpeg_std_error (&jerr.pub);\r
- jerr.pub.error_exit = my_jpeg_error_exit;\r
-\r
- if (setjmp (jerr.setjmp_buffer))\r
- {\r
- *pic = (unsigned char*)errormsg;\r
- jpeg_destroy_decompress (&cinfo);\r
- return -1;\r
- }\r
-\r
- jpeg_create_decompress (&cinfo);\r
- jpeg_buffer_src (&cinfo, src_buffer, src_size);\r
- jpeg_read_header (&cinfo, TRUE);\r
- jpeg_start_decompress (&cinfo);\r
-\r
- row_stride = cinfo.output_width * cinfo.output_components;\r
-\r
- size = cinfo.output_width * cinfo.output_height * 4;\r
- *width = cinfo.output_width;\r
- *height = cinfo.output_height;\r
- *pic = (unsigned char*) (g_malloc (size+1));\r
- memset (*pic, 0, size+1);\r
-\r
- buffer = (*cinfo.mem->alloc_sarray) ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);\r
-\r
- while (cinfo.output_scanline < cinfo.output_height)\r
- {\r
- jpeg_read_scanlines (&cinfo, buffer, 1);\r
-\r
- if (cinfo.out_color_components == 4)\r
- j_putRGBAScanline (buffer[0], cinfo.output_width, *pic, cinfo.output_scanline-1);\r
- else if (cinfo.out_color_components == 3)\r
- j_putRGBScanline (buffer[0], cinfo.output_width, *pic, cinfo.output_scanline-1);\r
- else if (cinfo.out_color_components == 1)\r
- j_putGrayScanlineToRGB (buffer[0], cinfo.output_width, *pic, cinfo.output_scanline-1);\r
- }\r
-\r
- jpeg_finish_decompress (&cinfo);\r
- jpeg_destroy_decompress (&cinfo);\r
-\r
- return 0;\r
-}\r
-\r
-void LoadJPG (const char *filename, unsigned char **pic, int *width, int *height)\r
-{\r
- unsigned char *fbuffer = NULL;\r
- int nLen = vfsLoadFile ((char *)filename, (void **)&fbuffer, 0 );\r
- if (nLen == -1)\r
- return;\r
-\r
- if (_LoadJPGBuff (fbuffer, nLen, pic, width, height) != 0)\r
- {\r
- g_FuncTable.m_pfnSysPrintf( "WARNING: JPEG library failed to load %s because %s\n", filename, *pic );\r
- *pic = NULL;\r
- }\r
-\r
- vfsFreeFile (fbuffer);\r
-}\r
+/*
+Copyright (c) 2001, Loki software, inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+Redistributions of source code must retain the above copyright notice, this list
+of conditions and the following disclaimer.
+
+Redistributions in binary form must reproduce the above copyright notice, this
+list of conditions and the following disclaimer in the documentation and/or
+other materials provided with the distribution.
+
+Neither the name of Loki software nor the names of its contributors may be used
+to endorse or promote products derived from this software without specific prior
+written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+DIRECT,INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+//
+// Functions to load JPEG files from a buffer, based on jdatasrc.c
+//
+// Leonardo Zide (leo@lokigames.com)
+//
+
+#include <stdio.h>
+#include <setjmp.h>
+#include <stdlib.h>
+#include <string.h>
+#include <glib.h>
+
+extern "C" {
+#include <jpeglib.h>
+#include <jerror.h>
+}
+
+#include "image.h"
+
+/* Expanded data source object for stdio input */
+
+typedef struct {
+ struct jpeg_source_mgr pub; /* public fields */
+
+ int src_size;
+ JOCTET * src_buffer;
+
+ JOCTET * buffer; /* start of buffer */
+ boolean start_of_file; /* have we gotten any data yet? */
+} my_source_mgr;
+
+typedef my_source_mgr * my_src_ptr;
+
+#define INPUT_BUF_SIZE 4096 /* choose an efficiently fread'able size */
+
+
+/*
+ * Initialize source --- called by jpeg_read_header
+ * before any data is actually read.
+ */
+
+static void my_init_source (j_decompress_ptr cinfo)
+{
+ my_src_ptr src = (my_src_ptr) cinfo->src;
+
+ /* We reset the empty-input-file flag for each image,
+ * but we don't clear the input buffer.
+ * This is correct behavior for reading a series of images from one source.
+ */
+ src->start_of_file = TRUE;
+}
+
+
+/*
+ * Fill the input buffer --- called whenever buffer is emptied.
+ *
+ * In typical applications, this should read fresh data into the buffer
+ * (ignoring the current state of next_input_byte & bytes_in_buffer),
+ * reset the pointer & count to the start of the buffer, and return TRUE
+ * indicating that the buffer has been reloaded. It is not necessary to
+ * fill the buffer entirely, only to obtain at least one more byte.
+ *
+ * There is no such thing as an EOF return. If the end of the file has been
+ * reached, the routine has a choice of ERREXIT() or inserting fake data into
+ * the buffer. In most cases, generating a warning message and inserting a
+ * fake EOI marker is the best course of action --- this will allow the
+ * decompressor to output however much of the image is there. However,
+ * the resulting error message is misleading if the real problem is an empty
+ * input file, so we handle that case specially.
+ *
+ * In applications that need to be able to suspend compression due to input
+ * not being available yet, a FALSE return indicates that no more data can be
+ * obtained right now, but more may be forthcoming later. In this situation,
+ * the decompressor will return to its caller (with an indication of the
+ * number of scanlines it has read, if any). The application should resume
+ * decompression after it has loaded more data into the input buffer. Note
+ * that there are substantial restrictions on the use of suspension --- see
+ * the documentation.
+ *
+ * When suspending, the decompressor will back up to a convenient restart point
+ * (typically the start of the current MCU). next_input_byte & bytes_in_buffer
+ * indicate where the restart point will be if the current call returns FALSE.
+ * Data beyond this point must be rescanned after resumption, so move it to
+ * the front of the buffer rather than discarding it.
+ */
+
+static boolean my_fill_input_buffer (j_decompress_ptr cinfo)
+{
+ my_src_ptr src = (my_src_ptr) cinfo->src;
+ size_t nbytes;
+
+ if (src->src_size > INPUT_BUF_SIZE)
+ nbytes = INPUT_BUF_SIZE;
+ else
+ nbytes = src->src_size;
+
+ memcpy (src->buffer, src->src_buffer, nbytes);
+ src->src_buffer += nbytes;
+ src->src_size -= nbytes;
+
+ if (nbytes <= 0) {
+ if (src->start_of_file) /* Treat empty input file as fatal error */
+ ERREXIT(cinfo, JERR_INPUT_EMPTY);
+ WARNMS(cinfo, JWRN_JPEG_EOF);
+ /* Insert a fake EOI marker */
+ src->buffer[0] = (JOCTET) 0xFF;
+ src->buffer[1] = (JOCTET) JPEG_EOI;
+ nbytes = 2;
+ }
+
+ src->pub.next_input_byte = src->buffer;
+ src->pub.bytes_in_buffer = nbytes;
+ src->start_of_file = FALSE;
+
+ return TRUE;
+}
+
+
+/*
+ * Skip data --- used to skip over a potentially large amount of
+ * uninteresting data (such as an APPn marker).
+ *
+ * Writers of suspendable-input applications must note that skip_input_data
+ * is not granted the right to give a suspension return. If the skip extends
+ * beyond the data currently in the buffer, the buffer can be marked empty so
+ * that the next read will cause a fill_input_buffer call that can suspend.
+ * Arranging for additional bytes to be discarded before reloading the input
+ * buffer is the application writer's problem.
+ */
+
+static void my_skip_input_data (j_decompress_ptr cinfo, long num_bytes)
+{
+ my_src_ptr src = (my_src_ptr) cinfo->src;
+
+ /* Just a dumb implementation for now. Could use fseek() except
+ * it doesn't work on pipes. Not clear that being smart is worth
+ * any trouble anyway --- large skips are infrequent.
+ */
+ if (num_bytes > 0) {
+ while (num_bytes > (long) src->pub.bytes_in_buffer) {
+ num_bytes -= (long) src->pub.bytes_in_buffer;
+ (void) my_fill_input_buffer(cinfo);
+ /* note we assume that fill_input_buffer will never return FALSE,
+ * so suspension need not be handled.
+ */
+ }
+ src->pub.next_input_byte += (size_t) num_bytes;
+ src->pub.bytes_in_buffer -= (size_t) num_bytes;
+ }
+}
+
+
+/*
+ * An additional method that can be provided by data source modules is the
+ * resync_to_restart method for error recovery in the presence of RST markers.
+ * For the moment, this source module just uses the default resync method
+ * provided by the JPEG library. That method assumes that no backtracking
+ * is possible.
+ */
+
+
+/*
+ * Terminate source --- called by jpeg_finish_decompress
+ * after all data has been read. Often a no-op.
+ *
+ * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
+ * application must deal with any cleanup that should happen even
+ * for error exit.
+ */
+
+static void my_term_source (j_decompress_ptr cinfo)
+{
+ /* no work necessary here */
+}
+
+
+/*
+ * Prepare for input from a stdio stream.
+ * The caller must have already opened the stream, and is responsible
+ * for closing it after finishing decompression.
+ */
+
+static void jpeg_buffer_src (j_decompress_ptr cinfo, void* buffer, int bufsize)
+{
+ my_src_ptr src;
+
+ /* The source object and input buffer are made permanent so that a series
+ * of JPEG images can be read from the same file by calling jpeg_stdio_src
+ * only before the first one. (If we discarded the buffer at the end of
+ * one image, we'd likely lose the start of the next one.)
+ * This makes it unsafe to use this manager and a different source
+ * manager serially with the same JPEG object. Caveat programmer.
+ */
+ if (cinfo->src == NULL) { /* first time for this JPEG object? */
+ cinfo->src = (struct jpeg_source_mgr *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
+ sizeof (my_source_mgr));
+ src = (my_src_ptr) cinfo->src;
+ src->buffer = (JOCTET *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
+ INPUT_BUF_SIZE * sizeof (JOCTET));
+ }
+
+ src = (my_src_ptr) cinfo->src;
+ src->pub.init_source = my_init_source;
+ src->pub.fill_input_buffer = my_fill_input_buffer;
+ src->pub.skip_input_data = my_skip_input_data;
+ src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
+ src->pub.term_source = my_term_source;
+ src->src_buffer = (JOCTET *)buffer;
+ src->src_size = bufsize;
+ src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
+ src->pub.next_input_byte = NULL; /* until buffer loaded */
+}
+
+// =============================================================================
+
+static char errormsg[JMSG_LENGTH_MAX];
+
+typedef struct my_jpeg_error_mgr
+{
+ struct jpeg_error_mgr pub; // "public" fields
+ jmp_buf setjmp_buffer; // for return to caller
+} bt_jpeg_error_mgr;
+
+static void my_jpeg_error_exit (j_common_ptr cinfo)
+{
+ my_jpeg_error_mgr* myerr = (bt_jpeg_error_mgr*) cinfo->err;
+
+ (*cinfo->err->format_message) (cinfo, errormsg);
+
+ longjmp (myerr->setjmp_buffer, 1);
+}
+
+// stash a scanline
+static void j_putRGBScanline (unsigned char* jpegline, int widthPix, unsigned char* outBuf, int row)
+{
+ int offset = row * widthPix * 4;
+ int count;
+
+ for (count = 0; count < widthPix; count++)
+ {
+ unsigned char iRed, iBlu, iGrn;
+ unsigned char *oRed, *oBlu, *oGrn, *oAlp;
+
+ iRed = *(jpegline + count * 3 + 0);
+ iGrn = *(jpegline + count * 3 + 1);
+ iBlu = *(jpegline + count * 3 + 2);
+
+ oRed = outBuf + offset + count * 4 + 0;
+ oGrn = outBuf + offset + count * 4 + 1;
+ oBlu = outBuf + offset + count * 4 + 2;
+ oAlp = outBuf + offset + count * 4 + 3;
+
+ *oRed = iRed;
+ *oGrn = iGrn;
+ *oBlu = iBlu;
+ *oAlp = 255;
+ }
+}
+
+// stash a scanline
+static void j_putRGBAScanline (unsigned char* jpegline, int widthPix, unsigned char* outBuf, int row)
+{
+ int offset = row * widthPix * 4;
+ int count;
+
+ for (count = 0; count < widthPix; count++)
+ {
+ unsigned char iRed, iBlu, iGrn, iAlp;
+ unsigned char *oRed, *oBlu, *oGrn, *oAlp;
+
+ iRed = *(jpegline + count * 4 + 0);
+ iGrn = *(jpegline + count * 4 + 1);
+ iBlu = *(jpegline + count * 4 + 2);
+ iAlp = *(jpegline + count * 4 + 3);
+
+ oRed = outBuf + offset + count * 4 + 0;
+ oGrn = outBuf + offset + count * 4 + 1;
+ oBlu = outBuf + offset + count * 4 + 2;
+ oAlp = outBuf + offset + count * 4 + 3;
+
+ *oRed = iRed;
+ *oGrn = iGrn;
+ *oBlu = iBlu;
+ // ydnar: see bug 900
+ *oAlp = 255; //% iAlp;
+ }
+}
+
+// stash a gray scanline
+static void j_putGrayScanlineToRGB (unsigned char* jpegline, int widthPix, unsigned char* outBuf, int row)
+{
+ int offset = row * widthPix * 4;
+ int count;
+
+ for (count = 0; count < widthPix; count++)
+ {
+ unsigned char iGray;
+ unsigned char *oRed, *oBlu, *oGrn, *oAlp;
+
+ // get our grayscale value
+ iGray = *(jpegline + count);
+
+ oRed = outBuf + offset + count * 4;
+ oGrn = outBuf + offset + count * 4 + 1;
+ oBlu = outBuf + offset + count * 4 + 2;
+ oAlp = outBuf + offset + count * 4 + 3;
+
+ *oRed = iGray;
+ *oGrn = iGray;
+ *oBlu = iGray;
+ *oAlp = 255;
+ }
+}
+
+static int LoadJPGBuff( void *src_buffer, int src_size, unsigned char **pic, int *width, int *height ) {
+ struct jpeg_decompress_struct cinfo;
+ struct my_jpeg_error_mgr jerr;
+ JSAMPARRAY buffer;
+ int row_stride, size;
+
+ cinfo.err = jpeg_std_error (&jerr.pub);
+ jerr.pub.error_exit = my_jpeg_error_exit;
+
+ if (setjmp (jerr.setjmp_buffer))
+ {
+ *pic = (unsigned char*)errormsg;
+ jpeg_destroy_decompress (&cinfo);
+ return -1;
+ }
+
+ jpeg_create_decompress (&cinfo);
+ jpeg_buffer_src (&cinfo, src_buffer, src_size);
+ jpeg_read_header (&cinfo, TRUE);
+ jpeg_start_decompress (&cinfo);
+
+ row_stride = cinfo.output_width * cinfo.output_components;
+
+ size = cinfo.output_width * cinfo.output_height * 4;
+ *width = cinfo.output_width;
+ *height = cinfo.output_height;
+ *pic = (unsigned char*) (g_malloc (size+1));
+ memset (*pic, 0, size+1);
+
+ buffer = (*cinfo.mem->alloc_sarray) ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
+
+ while (cinfo.output_scanline < cinfo.output_height)
+ {
+ jpeg_read_scanlines (&cinfo, buffer, 1);
+
+ if (cinfo.out_color_components == 4)
+ j_putRGBAScanline (buffer[0], cinfo.output_width, *pic, cinfo.output_scanline-1);
+ else if (cinfo.out_color_components == 3)
+ j_putRGBScanline (buffer[0], cinfo.output_width, *pic, cinfo.output_scanline-1);
+ else if (cinfo.out_color_components == 1)
+ j_putGrayScanlineToRGB (buffer[0], cinfo.output_width, *pic, cinfo.output_scanline-1);
+ }
+
+ jpeg_finish_decompress (&cinfo);
+ jpeg_destroy_decompress (&cinfo);
+
+ return 0;
+}
+
+void LoadJPG( const char *filename, unsigned char **pic, int *width, int *height ) {
+ unsigned char *fbuffer = NULL;
+ int nLen = vfsLoadFile ((char *)filename, (void **)&fbuffer, 0 );
+ if (nLen == -1)
+ return;
+
+ if ( LoadJPGBuff( fbuffer, nLen, pic, width, height ) != 0 ) {
+ g_FuncTable.m_pfnSysPrintf( "WARNING: JPEG library failed to load %s because %s\n", filename, *pic );
+ *pic = NULL;
+ }
+
+ vfsFreeFile( fbuffer );
+}