X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;f=images%2Fio-libungif.c;h=bf97f743e11b5f009b1608090fa0bdcd98c8b467;hb=1481eca416a467e9952dbc5e4852afe66eaf1256;hp=0cc2622d2ffc96e48938d74cd120daa64feab41a;hpb=966305189fb3c543170117da57f110a8e9851ac2;p=libucw.git

diff --git a/images/io-libungif.c b/images/io-libungif.c
index 0cc2622d..bf97f743 100644
--- a/images/io-libungif.c
+++ b/images/io-libungif.c
@@ -7,20 +7,287 @@
  *	of the GNU Lesser General Public License.
  */
 
-#define LOCAL_DEBUG
+#undef LOCAL_DEBUG
 
-#include "lib/lib.h"
-#include "images/images.h"
+#include <ucw/lib.h>
+#include <ucw/mempool.h>
+#include <ucw/fastbuf.h>
+#include <images/images.h>
+#include <images/error.h>
+#include <images/color.h>
+#include <images/io-main.h>
+
+#include <gif_lib.h>
+
+struct libungif_read_data {
+  GifFileType *gif;
+  int transparent_index;
+};
+
+static int
+libungif_read_func(GifFileType *gif, GifByteType *ptr, int len)
+{
+  DBG("libungif_read_func(len=%d)", len);
+  return bread((struct fastbuf *)gif->UserData, (byte *)ptr, len);
+}
+
+static void
+libungif_read_cancel(struct image_io *io)
+{
+  DBG("libungif_read_cancel()");
+
+  struct libungif_read_data *rd = io->read_data;
+  DGifCloseFile(rd->gif);
+}
 
 int
 libungif_read_header(struct image_io *io)
 {
-  image_thread_err(io->thread, IMAGE_ERR_NOT_IMPLEMENTED, "Libungif read not implemented.");
-  return 0;
+  DBG("libungif_read_header()");
+
+  /* Create libungif structure */
+  GifFileType *gif;
+  if (unlikely(!(gif = DGifOpen(io->fastbuf, libungif_read_func))))
+    {
+      IMAGE_ERROR(io->context, IMAGE_ERROR_READ_FAILED, "Cannot create libungif structure.");
+      return 0;
+    }
+
+  struct libungif_read_data *rd = io->read_data = mp_alloc(io->internal_pool, sizeof(*rd));
+  rd->gif = gif;
+
+  DBG("executing DGifSlurp()");
+  if (unlikely(DGifSlurp(gif) != GIF_OK))
+    {
+      IMAGE_ERROR(io->context, IMAGE_ERROR_READ_FAILED, "Gif read failed.");
+      DGifCloseFile(gif);
+      return 0;
+    }
+
+  DBG("ImageCount=%d ColorResolution=%d SBackGroundColor=%d SColorMap=%p", gif->ImageCount, gif->SColorResolution, gif->SBackGroundColor, gif->SColorMap);
+  if (unlikely(!gif->ImageCount))
+    {
+      IMAGE_ERROR(io->context, IMAGE_ERROR_READ_FAILED, "There are no images in gif file.");
+      DGifCloseFile(gif);
+      return 0;
+    }
+
+  /* Read image parameters */
+  SavedImage *image = gif->SavedImages;
+  if (unlikely(image->ImageDesc.Width <= 0 || image->ImageDesc.Height <= 0 ||
+      image->ImageDesc.Width > (int)image_max_dim || image->ImageDesc.Height > (int)image_max_dim))
+    {
+      IMAGE_ERROR(io->context, IMAGE_ERROR_INVALID_DIMENSIONS, "Invalid gif dimensions.");
+      DGifCloseFile(gif);
+      return 0;
+    }
+  ColorMapObject *color_map = image->ImageDesc.ColorMap ? : gif->SColorMap;
+  if (unlikely(!color_map))
+    {
+      IMAGE_ERROR(io->context, IMAGE_ERROR_READ_FAILED, "Missing palette.");
+      DGifCloseFile(gif);
+      return 0;
+    }
+  io->cols = image->ImageDesc.Width;
+  io->rows = image->ImageDesc.Height;
+  if (unlikely((io->number_of_colors = color_map->ColorCount) > 256))
+    {
+      IMAGE_ERROR(io->context, IMAGE_ERROR_READ_FAILED, "Too many gif colors.");
+      DGifCloseFile(gif);
+      return 0;
+    }
+  io->flags = COLOR_SPACE_RGB | IMAGE_IO_HAS_PALETTE;
+
+  /* Search extension blocks */
+  rd->transparent_index = -1;
+  for (int i = 0; i < image->ExtensionBlockCount; i++)
+    {
+      ExtensionBlock *e = image->ExtensionBlocks + i;
+      if (e->Function == 0xF9)
+        {
+	  DBG("Found graphics control extension");
+	  if (unlikely(e->ByteCount != 4))
+	    {
+              IMAGE_ERROR(io->context, IMAGE_ERROR_READ_FAILED, "Invalid graphics control extension.");
+              DGifCloseFile(gif);
+              return 0;
+	    }
+	  byte *b = e->Bytes;
+	  /* transparent color present */
+	  if (b[0] & 1)
+	    {
+	      rd->transparent_index = b[3];
+	      io->flags |= IMAGE_ALPHA;
+	      if (gif->SColorMap)
+	        {
+                  GifColorType *background = color_map->Colors + gif->SBackGroundColor;
+                  color_make_rgb(&io->background_color, background->Red, background->Green, background->Blue);
+		}
+	    }
+	  /* We've got everything we need :-) */
+	  break;
+	}
+      else
+	DBG("Found unknown extension: type=%d size=%d", e->Function, e->ByteCount);
+    }
+
+  /* Success */
+  io->read_cancel = libungif_read_cancel;
+  return 1;
 }
 
 int
-libungif_read_data(struct image_io *io UNUSED)
+libungif_read_data(struct image_io *io)
 {
-  ASSERT(0);
+  DBG("libungif_read_data()");
+
+  struct libungif_read_data *rd = io->read_data;
+  GifFileType *gif = rd->gif;
+  SavedImage *image = gif->SavedImages;
+
+  /* Prepare image */
+  struct image_io_read_data_internals rdi;
+  uint read_flags = io->flags;
+  uint cs = read_flags & IMAGE_COLOR_SPACE;
+  if (cs != COLOR_SPACE_GRAYSCALE && cs != COLOR_SPACE_RGB)
+    read_flags = (read_flags & ~IMAGE_COLOR_SPACE & IMAGE_CHANNELS_FORMAT) | COLOR_SPACE_RGB;
+  if (unlikely(!image_io_read_data_prepare(&rdi, io, image->ImageDesc.Width, image->ImageDesc.Height, read_flags)))
+    {
+      DGifCloseFile(gif);
+      return 0;
+    }
+
+  /* Get pixels and palette */
+  byte *pixels = (byte *)image->RasterBits;
+  ColorMapObject *color_map = image->ImageDesc.ColorMap ? : gif->SColorMap;
+  GifColorType *palette = color_map->Colors;
+  byte *img_end = rdi.image->pixels + rdi.image->image_size;
+
+  /* Handle deinterlacing */
+  uint dein_step, dein_next;
+  if (image->ImageDesc.Interlace)
+    {
+      DBG("Deinterlaced image");
+      dein_step = dein_next = rdi.image->row_size << 3;
+    }
+  else
+    dein_step = dein_next = rdi.image->row_size;
+
+  /* Convert pixels */
+  switch (rdi.image->pixel_size)
+    {
+      case 1:
+	{
+	  byte pal[256], *pal_pos = pal, *pal_end = pal + 256;
+	  for (uint i = 0; i < (uint)color_map->ColorCount; i++, pal_pos++, palette++)
+	    *pal_pos = rgb_to_gray_func(palette->Red, palette->Green, palette->Blue);
+	  if (pal_pos != pal_end)
+	    bzero(pal_pos, pal_end - pal_pos);
+	  if (rd->transparent_index >= 0 && (io->flags & IMAGE_IO_USE_BACKGROUND))
+	    if (!color_put(io->context, &io->background_color, pal + rd->transparent_index, COLOR_SPACE_GRAYSCALE))
+	      {
+		DGifCloseFile(gif);
+		return 0;
+	      }
+#	  define DO_ROW_END do{ \
+	      walk_row_start += dein_step; \
+	      while (walk_row_start >= img_end) \
+		{ uint n = dein_next >> 1; walk_row_start = rdi.image->pixels + n, dein_step = dein_next; dein_next = n; } \
+	    }while(0)
+#	  define IMAGE_WALK_PREFIX(x) walk_##x
+#	  define IMAGE_WALK_INLINE
+#	  define IMAGE_WALK_IMAGE (rdi.image)
+#	  define IMAGE_WALK_UNROLL 4
+#	  define IMAGE_WALK_COL_STEP 1
+#	  define IMAGE_WALK_ROW_STEP 0
+#	  define IMAGE_WALK_DO_STEP do{ *walk_pos = pal[*pixels++]; }while(0)
+#	  define IMAGE_WALK_DO_ROW_END DO_ROW_END
+#	  include <images/image-walk.h>
+	  break;
+	}
+      case 2:
+	{
+	  byte pal[256 * 2], *pal_pos = pal, *pal_end = pal + 256 * 2;
+	  for (uint i = 0; i < (uint)color_map->ColorCount; i++, pal_pos += 2, palette++)
+	    {
+	      pal_pos[0] = rgb_to_gray_func(palette->Red, palette->Green, palette->Blue);
+	      pal_pos[1] = 255;
+	    }
+	  if (pal_pos != pal_end)
+	    bzero(pal_pos, pal_end - pal_pos);
+	  if (rd->transparent_index >= 0)
+	    pal[rd->transparent_index * 2 + 1] = 0;
+#	  define IMAGE_WALK_PREFIX(x) walk_##x
+#	  define IMAGE_WALK_INLINE
+#	  define IMAGE_WALK_IMAGE (rdi.image)
+#	  define IMAGE_WALK_UNROLL 4
+#	  define IMAGE_WALK_COL_STEP 2
+#	  define IMAGE_WALK_ROW_STEP 0
+#	  define IMAGE_WALK_DO_STEP do{ *(u16 *)walk_pos = ((u16 *)pal)[*pixels++]; }while(0)
+#	  define IMAGE_WALK_DO_ROW_END DO_ROW_END
+#	  include <images/image-walk.h>
+	  break;
+	}
+      case 3:
+	{
+	  byte pal[256 * 4], *pal_pos = pal, *pal_end = pal + 256 * 4;
+	  for (uint i = 0; i < (uint)color_map->ColorCount; i++, pal_pos += 4, palette++)
+	    {
+	      pal_pos[0] = palette->Red;
+	      pal_pos[1] = palette->Green;
+	      pal_pos[2] = palette->Blue;
+	    }
+	  if (pal_pos != pal_end)
+	    bzero(pal_pos, pal_end - pal_pos);
+	  if (rd->transparent_index >= 0 && (io->flags & IMAGE_IO_USE_BACKGROUND))
+	    if (!color_put(io->context, &io->background_color, pal + 4 * rd->transparent_index, COLOR_SPACE_RGB))
+	      {
+		DGifCloseFile(gif);
+		return 0;
+	      }
+#	  define IMAGE_WALK_PREFIX(x) walk_##x
+#	  define IMAGE_WALK_INLINE
+#	  define IMAGE_WALK_IMAGE (rdi.image)
+#	  define IMAGE_WALK_UNROLL 4
+#	  define IMAGE_WALK_COL_STEP 3
+#	  define IMAGE_WALK_ROW_STEP 0
+#	  define IMAGE_WALK_DO_STEP do{ byte *p = pal + 4 * (*pixels++); walk_pos[0] = p[0]; walk_pos[1] = p[1]; walk_pos[2] = p[2]; }while(0)
+#	  define IMAGE_WALK_DO_ROW_END DO_ROW_END
+#	  include <images/image-walk.h>
+	  break;
+	}
+      case 4:
+	{
+	  byte pal[256 * 4], *pal_pos = pal, *pal_end = pal + 256 * 4;
+	  for (uint i = 0; i < (uint)color_map->ColorCount; i++, pal_pos += 4, palette++)
+	    {
+	      pal_pos[0] = palette->Red;
+	      pal_pos[1] = palette->Green;
+	      pal_pos[2] = palette->Blue;
+	      pal_pos[3] = 255;
+	    }
+	  if (pal_pos != pal_end)
+	    bzero(pal_pos, pal_end - pal_pos);
+	  if (rd->transparent_index >= 0)
+	    pal[rd->transparent_index * 4 + 3] = 0;
+#	  define IMAGE_WALK_PREFIX(x) walk_##x
+#	  define IMAGE_WALK_INLINE
+#	  define IMAGE_WALK_IMAGE (rdi.image)
+#	  define IMAGE_WALK_UNROLL 4
+#	  define IMAGE_WALK_COL_STEP 4
+#	  define IMAGE_WALK_ROW_STEP 0
+#	  define IMAGE_WALK_DO_STEP do{ *(u32 *)walk_pos = ((u32 *)pal)[*pixels++]; }while(0)
+#	  define IMAGE_WALK_DO_ROW_END DO_ROW_END
+#	  include <images/image-walk.h>
+	  break;
+	}
+      default:
+        ASSERT(0);
+    }
+
+  /* Destroy libungif structure */
+  DGifCloseFile(gif);
+
+  /* Finish image */
+  return image_io_read_data_finish(&rdi, io);
 }