/******************************************************************************
* This routine should be called before any attemp to read an image. *
* Note it is assumed the Image desc. header (',') has been read. *
******************************************************************************/
int DGifGetImageDesc(GifFileType *GifFile)
{
int i, BitsPerPixel;
GifByteType Buf[3];
GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
if (!IS_READABLE(Private)) {
/* This file was NOT open for reading: */
_GifError = D_GIF_ERR_NOT_READABLE;
return GIF_ERROR;
}
if (DGifGetWord(Private, &GifFile->Image.Left) == GIF_ERROR ||
DGifGetWord(Private, &GifFile->Image.Top) == GIF_ERROR ||
DGifGetWord(Private, &GifFile->Image.Width) == GIF_ERROR ||
DGifGetWord(Private, &GifFile->Image.Height) == GIF_ERROR)
return GIF_ERROR;
if (my_fread(Buf, 1, 1, Private) != 1) {
_GifError = D_GIF_ERR_READ_FAILED;
return GIF_ERROR;
}
BitsPerPixel = (Buf[0] & 0x07) + 1;
GifFile->Image.Interlace = (Buf[0] & 0x40);
if (Buf[0] & 0x80) { /* Does this image have local color map? */
if (GifFile->Image.ColorMap)
FreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = MakeMapObject(1 << BitsPerPixel, NULL);
/* Get the image local color map: */
for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++) {
if (my_fread(Buf, 1, 3, Private) != 3) {
_GifError = D_GIF_ERR_READ_FAILED;
return GIF_ERROR;
}
GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
}
}
GifFile->ImageCount++;
Private->PixelCount = (s32) GifFile->Image.Width *
(s32) GifFile->Image.Height;
DGifSetupDecompress(GifFile); /* Reset decompress algorithm parameters. */
return GIF_OK;
}
static int DGifGetImageDesc(GifFileType * GifFile)
{
int i, BitsPerPixel;
GifByteType Buf[3];
GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
SavedImage *sp;
if (!IS_READABLE(Private))
{
_GifError = D_GIF_ERR_NOT_READABLE;
return GIF_ERROR;
}
if (DGifGetWord(GifFile, &GifFile->Image.Left) == GIF_ERROR || DGifGetWord(GifFile, &GifFile->Image.Top) == GIF_ERROR || DGifGetWord(GifFile, &GifFile->Image.Width) == GIF_ERROR
|| DGifGetWord(GifFile, &GifFile->Image.Height) == GIF_ERROR)
return GIF_ERROR;
if (READ(GifFile, Buf, 1) != 1)
{
_GifError = D_GIF_ERR_READ_FAILED;
return GIF_ERROR;
}
BitsPerPixel = (Buf[0] & 0x07) + 1;
GifFile->Image.Interlace = (Buf[0] & 0x40);
if (Buf[0] & 0x80)
{
if (GifFile->Image.ColorMap && GifFile->SavedImages == NULL)
FreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = MakeMapObject(1 << BitsPerPixel, NULL);
if (GifFile->Image.ColorMap == NULL)
{
_GifError = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++)
{
if (READ(GifFile, Buf, 3) != 3)
{
FreeMapObject(GifFile->Image.ColorMap);
_GifError = D_GIF_ERR_READ_FAILED;
GifFile->Image.ColorMap = NULL;
return GIF_ERROR;
}
GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
}
}
else if (GifFile->Image.ColorMap)
{
FreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
}
if (GifFile->SavedImages)
{
if ((GifFile->SavedImages = (SavedImage *) realloc(GifFile->SavedImages, sizeof(SavedImage) * (GifFile->ImageCount + 1))) == NULL)
{
_GifError = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
else
{
if ((GifFile->SavedImages = (SavedImage *) gif_malloc(sizeof(SavedImage))) == NULL)
{
_GifError = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
sp = &GifFile->SavedImages[GifFile->ImageCount];
memcpy(&sp->ImageDesc, &GifFile->Image, sizeof(GifImageDesc));
if (GifFile->Image.ColorMap != NULL)
{
sp->ImageDesc.ColorMap = MakeMapObject(GifFile->Image.ColorMap->ColorCount, GifFile->Image.ColorMap->Colors);
if (sp->ImageDesc.ColorMap == NULL)
{
_GifError = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
sp->RasterBits = (unsigned char *) NULL;
sp->ExtensionBlockCount = 0;
sp->ExtensionBlocks = (ExtensionBlock *) NULL;
GifFile->ImageCount++;
Private->PixelCount = (long) GifFile->Image.Width * (long) GifFile->Image.Height;
DGifSetupDecompress(GifFile);
return GIF_OK;
}
/******************************************************************************
This routine should be called before any attempt to read an image.
Note it is assumed the Image desc. header has been read.
******************************************************************************/
int
DGifGetImageDesc(GifFileType *GifFile)
{
unsigned int BitsPerPixel;
GifByteType Buf[3];
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
SavedImage *sp;
if (!IS_READABLE(Private)) {
/* This file was NOT open for reading: */
GifFile->Error = D_GIF_ERR_NOT_READABLE;
return GIF_ERROR;
}
if (DGifGetWord(GifFile, &GifFile->Image.Left) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Top) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Width) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Height) == GIF_ERROR)
return GIF_ERROR;
if (READ(GifFile, Buf, 1) != 1) {
GifFile->Error = D_GIF_ERR_READ_FAILED;
GifFreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
return GIF_ERROR;
}
BitsPerPixel = (Buf[0] & 0x07) + 1;
GifFile->Image.Interlace = (Buf[0] & 0x40) ? giftrue : giffalse;
/* Setup the colormap */
if (GifFile->Image.ColorMap) {
GifFreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
}
/* Does this image have local color map? */
if (Buf[0] & 0x80) {
unsigned int i;
GifFile->Image.ColorMap = GifMakeMapObject(1 << BitsPerPixel, NULL);
if (GifFile->Image.ColorMap == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
/* Get the image local color map: */
for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++) {
if (READ(GifFile, Buf, 3) != 3) {
GifFreeMapObject(GifFile->Image.ColorMap);
GifFile->Error = D_GIF_ERR_READ_FAILED;
GifFile->Image.ColorMap = NULL;
return GIF_ERROR;
}
GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
}
}
if (GifFile->SavedImages) {
if ((GifFile->SavedImages = (SavedImage *)realloc(GifFile->SavedImages,
sizeof(SavedImage) *
(GifFile->ImageCount + 1))) == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
} else {
if ((GifFile->SavedImages =
(SavedImage *) malloc(sizeof(SavedImage))) == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
sp = &GifFile->SavedImages[GifFile->ImageCount];
memcpy(&sp->ImageDesc, &GifFile->Image, sizeof(GifImageDesc));
if (GifFile->Image.ColorMap != NULL) {
sp->ImageDesc.ColorMap = GifMakeMapObject(
GifFile->Image.ColorMap->ColorCount,
GifFile->Image.ColorMap->Colors);
if (sp->ImageDesc.ColorMap == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
sp->RasterBits = (unsigned char *)NULL;
sp->ExtensionBlockCount = 0;
sp->ExtensionBlocks = (ExtensionBlock *) NULL;
GifFile->ImageCount++;
Private->PixelCount = (long)GifFile->Image.Width *
(long)GifFile->Image.Height;
/* Reset decompress algorithm parameters. */
(void)DGifSetupDecompress(GifFile);
return GIF_OK;
}
/******************************************************************************
* This routine should be called before any attempt to read an image.
* Note it is assumed the Image desc. header (',') has been read.
*****************************************************************************/
static int
DGifGetImageDesc(GifFileType * GifFile) {
int i, BitsPerPixel, SortFlag;
GifByteType Buf[3];
GifFilePrivateType *Private = GifFile->Private;
SavedImage *sp;
if (DGifGetWord(GifFile, &GifFile->Image.Left) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Top) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Width) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Height) == GIF_ERROR)
return GIF_ERROR;
if (READ(GifFile, Buf, 1) != 1) {
return GIF_ERROR;
}
BitsPerPixel = (Buf[0] & 0x07) + 1;
SortFlag = (Buf[0] & 0x20) != 0;
GifFile->Image.Interlace = (Buf[0] & 0x40);
if (Buf[0] & 0x80) { /* Does this image have local color map? */
FreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = MakeMapObject(1 << BitsPerPixel, NULL);
if (GifFile->Image.ColorMap == NULL) {
return GIF_ERROR;
}
/* Get the image local color map: */
GifFile->Image.ColorMap->SortFlag = SortFlag;
for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++) {
if (READ(GifFile, Buf, 3) != 3) {
FreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
return GIF_ERROR;
}
GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
}
} else if (GifFile->Image.ColorMap) {
FreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
}
if (GifFile->SavedImages) {
if ((GifFile->SavedImages = ungif_realloc(GifFile->SavedImages,
sizeof(SavedImage) *
(GifFile->ImageCount + 1))) == NULL) {
return GIF_ERROR;
}
} else {
if ((GifFile->SavedImages = ungif_alloc(sizeof(SavedImage))) == NULL) {
return GIF_ERROR;
}
}
sp = &GifFile->SavedImages[GifFile->ImageCount];
sp->ImageDesc = GifFile->Image;
if (GifFile->Image.ColorMap != NULL) {
sp->ImageDesc.ColorMap = MakeMapObject(
GifFile->Image.ColorMap->ColorCount,
GifFile->Image.ColorMap->Colors);
if (sp->ImageDesc.ColorMap == NULL) {
return GIF_ERROR;
}
sp->ImageDesc.ColorMap->SortFlag = GifFile->Image.ColorMap->SortFlag;
}
sp->RasterBits = NULL;
sp->Extensions.ExtensionBlockCount = 0;
sp->Extensions.ExtensionBlocks = NULL;
GifFile->ImageCount++;
Private->PixelCount = (long)GifFile->Image.Width *
(long)GifFile->Image.Height;
DGifSetupDecompress(GifFile); /* Reset decompress algorithm parameters. */
return GIF_OK;
}
//读取单个帧的图片信息(图片的上下左右坐标，帧的局部颜色空间等)
int
DGifGetImageDesc(GifFileType *GifFile)
{
unsigned int BitsPerPixel;
GifByteType Buf[3];
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
SavedImage *sp;
if (!IS_READABLE(Private)) {
/* This file was NOT open for reading: */
GifFile->Error = D_GIF_ERR_NOT_READABLE;
return GIF_ERROR;
}
//读取当前帧的上下左右坐标
if (DGifGetWord(GifFile, &GifFile->Image.Left) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Top) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Width) == GIF_ERROR ||
DGifGetWord(GifFile, &GifFile->Image.Height) == GIF_ERROR)
return GIF_ERROR;
//读取长度1字节的信息(即当前帧的Packed Field)
if (READ(GifFile, Buf, 1) != 1) {
GifFile->Error = D_GIF_ERR_READ_FAILED;
GifFreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
return GIF_ERROR;
}
//局部颜色空间的大小
BitsPerPixel = (Buf[0] & 0x07) + 1;
//判断当前帧是否交错模式
GifFile->Image.Interlace = (Buf[0] & 0x40) ? true : false;
/* Setup the colormap */
if (GifFile->Image.ColorMap) {
GifFreeMapObject(GifFile->Image.ColorMap);
GifFile->Image.ColorMap = NULL;
}
//判断当前帧是否使用局部的颜色空间
if (Buf[0] & 0x80) {
unsigned int i;
GifFile->Image.ColorMap = GifMakeMapObject(1 << BitsPerPixel, NULL);
if (GifFile->Image.ColorMap == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
//获取局部颜色空间 并储存到临时的帧描述内
for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++) {
/* coverity[check_return] */
if (READ(GifFile, Buf, 3) != 3) {
GifFreeMapObject(GifFile->Image.ColorMap);
GifFile->Error = D_GIF_ERR_READ_FAILED;
GifFile->Image.ColorMap = NULL;
return GIF_ERROR;
}
GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
}
}
//判断之前是否已经有储存帧图像
if (GifFile->SavedImages) {
//如果有已经储存的帧图像 需要重新分配空间
SavedImage* new_saved_images =
(SavedImage *)realloc(GifFile->SavedImages,
sizeof(SavedImage) * (GifFile->ImageCount + 1));
if (new_saved_images == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
GifFile->SavedImages = new_saved_images;
} else {
if ((GifFile->SavedImages =
(SavedImage *) malloc(sizeof(SavedImage))) == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
//指向新的SavedImage
sp = &GifFile->SavedImages[GifFile->ImageCount];
//写入之前获取的帧图像描述
memcpy(&sp->ImageDesc, &GifFile->Image, sizeof(GifImageDesc));
//写入局部颜色空间
if (GifFile->Image.ColorMap != NULL) {
sp->ImageDesc.ColorMap = GifMakeMapObject(
GifFile->Image.ColorMap->ColorCount,
GifFile->Image.ColorMap->Colors);
if (sp->ImageDesc.ColorMap == NULL) {
GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
return GIF_ERROR;
}
}
sp->RasterBits = (unsigned char *)NULL;
sp->ExtensionBlockCount = 0;
sp->ExtensionBlocks = (ExtensionBlock *) NULL;
GifFile->ImageCount++;
Private->PixelCount = (long)GifFile->Image.Width *
(long)GifFile->Image.Height;
/* Reset decompress algorithm parameters. */
//DGifSetupDecompress
return DGifSetupDecompress(GifFile);
}