wrlib: Renamed image format related files for clarity

This patch makes all files appear together when listing files and it is more clear about their function. Signed-off-by: Christophe CURIS <christophe.curis@free.fr>
2025-12-21 05:18:06 +01:00 · 2013-11-08 18:50:03 +01:00
parent f619546af9
commit c3a132215d
8 changed files with 7 additions and 7 deletions
--- a/wrlib/load_gif.c
+++ b/wrlib/load_gif.c
@@ -0,0 +1,222 @@
+/* gif.c - load GIF image from file
+ *
+ * Raster graphics library
+ *
+ * Copyright (c) 1998-2003 Alfredo K. Kojima
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public
+ *  License along with this library; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ *  MA 02110-1301, USA.
+ */
+
+#include <config.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <gif_lib.h>
+
+#include "wraster.h"
+#include "imgformat.h"
+
+static int InterlacedOffset[] = { 0, 4, 2, 1 };
+static int InterlacedJumps[] = { 8, 8, 4, 2 };
+
+/*
+ * Partially based on code in gif2rgb from giflib, by Gershon Elber.
+ */
+RImage *RLoadGIF(const char *file, int index)
+{
+	RImage *image = NULL;
+	unsigned char *cptr;
+	GifFileType *gif = NULL;
+	GifPixelType *buffer = NULL;
+	int i, j, k;
+	int width, height;
+	GifRecordType recType;
+	ColorMapObject *colormap;
+	unsigned char rmap[256], gmap[256], bmap[256];
+	int gif_error;
+
+	if (index < 0)
+		index = 0;
+
+	/* default error message */
+	RErrorCode = RERR_BADINDEX;
+
+#if USE_GIF == 4
+	gif = DGifOpenFileName(file);
+#else /* USE_GIF == 5 */
+	gif = DGifOpenFileName(file, &gif_error);
+#endif
+
+	if (!gif) {
+#if USE_GIF == 4
+		gif_error = GifLastError();
+#endif
+		switch (gif_error) {
+		case D_GIF_ERR_OPEN_FAILED:
+			RErrorCode = RERR_OPEN;
+			break;
+		case D_GIF_ERR_READ_FAILED:
+			RErrorCode = RERR_READ;
+			break;
+		default:
+			RErrorCode = RERR_BADIMAGEFILE;
+			break;
+		}
+		return NULL;
+	}
+
+	if (gif->SWidth < 1 || gif->SHeight < 1) {
+		DGifCloseFile(gif);
+		RErrorCode = RERR_BADIMAGEFILE;
+		return NULL;
+	}
+
+	colormap = gif->SColorMap;
+	i = 0;
+
+	do {
+		int extCode;
+		GifByteType *extension;
+
+		if (DGifGetRecordType(gif, &recType) == GIF_ERROR)
+			goto giferr;
+
+		switch (recType) {
+		case IMAGE_DESC_RECORD_TYPE:
+			if (i++ != index)
+				break;
+
+			if (DGifGetImageDesc(gif) == GIF_ERROR)
+				goto giferr;
+
+			width = gif->Image.Width;
+			height = gif->Image.Height;
+
+			if (gif->Image.ColorMap)
+				colormap = gif->Image.ColorMap;
+
+			/* the gif specs talk about a default colormap, but it
+			 * doesnt say what the heck is this default colormap
+			 * Render anything */
+			if (colormap) {
+				for (j = 0; j < colormap->ColorCount; j++) {
+					rmap[j] = colormap->Colors[j].Red;
+					gmap[j] = colormap->Colors[j].Green;
+					bmap[j] = colormap->Colors[j].Blue;
+				}
+			}
+
+			buffer = malloc(width * sizeof(GifColorType));
+			if (!buffer) {
+				RErrorCode = RERR_NOMEMORY;
+				goto bye;
+			}
+
+			image = RCreateImage(width, height, False);
+			if (!image)
+				goto bye;
+
+			if (gif->Image.Interlace) {
+				int l, pelsPerLine;
+
+				if (RRGBAFormat == image->format)
+					pelsPerLine = width * 4;
+				else
+					pelsPerLine = width * 3;
+
+				for (j = 0; j < 4; j++) {
+					for (k = InterlacedOffset[j]; k < height; k += InterlacedJumps[j]) {
+						if (DGifGetLine(gif, buffer, width) == GIF_ERROR)
+							goto giferr;
+
+						cptr = image->data + (k * pelsPerLine);
+						for (l = 0; l < width; l++) {
+							int pixel = buffer[l];
+							*cptr++ = rmap[pixel];
+							*cptr++ = gmap[pixel];
+							*cptr++ = bmap[pixel];
+						}
+					}
+				}
+			} else {
+				cptr = image->data;
+				for (j = 0; j < height; j++) {
+					if (DGifGetLine(gif, buffer, width) == GIF_ERROR)
+						goto giferr;
+
+					for (k = 0; k < width; k++) {
+						int pixel = buffer[k];
+						*cptr++ = rmap[pixel];
+						*cptr++ = gmap[pixel];
+						*cptr++ = bmap[pixel];
+						if (RRGBAFormat == image->format)
+							cptr++;
+					}
+				}
+			}
+			break;
+
+		case EXTENSION_RECORD_TYPE:
+			/* skip all extension blocks */
+			if (DGifGetExtension(gif, &extCode, &extension) == GIF_ERROR)
+				goto giferr;
+
+			while (extension)
+				if (DGifGetExtensionNext(gif, &extension) == GIF_ERROR)
+					goto giferr;
+
+			break;
+
+		default:
+			break;
+		}
+	} while (recType != TERMINATE_RECORD_TYPE && i <= index);
+
+	/* yuck! */
+	goto did_not_get_any_errors;
+ giferr:
+#if USE_GIF == 4
+	switch (GifLastError()) {
+	case D_GIF_ERR_OPEN_FAILED:
+		RErrorCode = RERR_OPEN;
+		break;
+	case D_GIF_ERR_READ_FAILED:
+		RErrorCode = RERR_READ;
+		break;
+	default:
+		RErrorCode = RERR_BADIMAGEFILE;
+		break;
+	}
+#else
+	/* With gif_lib v5 there's no way to know what went wrong */
+	RErrorCode = RERR_BADIMAGEFILE;
+#endif
+ bye:
+	if (image)
+		RReleaseImage(image);
+	image = NULL;
+ did_not_get_any_errors:
+
+	if (buffer)
+		free(buffer);
+
+	if (gif)
+		DGifCloseFile(gif);
+
+	return image;
+}