winamp/Src/gif/GIFLoader.cpp
2024-09-24 14:54:57 +02:00

127 lines
3 KiB
C++

#include "GIFLoader.h"
#include "api__gif.h"
#include <wchar.h>
#include <bfc/platform/strcmp.h>
extern "C" {
#include "../giflib/gif_lib.h"
};
static bool StringEnds(const wchar_t *a, const wchar_t *b)
{
size_t aLen = wcslen(a);
size_t bLen = wcslen(b);
if (aLen < bLen) return false; // too short
return !_wcsicmp(a + aLen - bLen, b);
}
int GIFLoader::isMine(const wchar_t *filename)
{
return (filename && StringEnds(filename, L".GIF"));
}
int GIFLoader::getHeaderSize()
{
return 3;
}
const wchar_t *GIFLoader::mimeType()
{
return L"image/gif";
}
int GIFLoader::testData(const void *data, int datalen)
{
if(datalen >= 3 && strncmp((const char*)data,"GIF",3)==0) return 1;
return 0;
}
typedef struct {
BYTE * data;
int len;
} readStruct;
extern "C" int myreader(GifFileType *gif, GifByteType *data, int len) {
readStruct* r = (readStruct*)gif->UserData;
int l = min(len,r->len);
if(l == 0) return 0;
memcpy(data,r->data,l);
r->len -= l;
r->data += l;
return l;
}
ARGB32 *GIFLoader::loadImage(const void *datain, int datalen, int *w, int *h, ifc_xmlreaderparams *params)
{
readStruct read = {(BYTE*)datain,datalen};
int* l_error = NULL;
GifFileType * gif = DGifOpen(&read, myreader, l_error);
if(!gif) return 0;
if(!DGifSlurp(gif) || !gif->ImageCount) { DGifCloseFile(gif, l_error); return 0; }
ColorMapObject *map = gif->SColorMap;
if(!map) map = gif->SavedImages[0].ImageDesc.ColorMap;
if(!map) { DGifCloseFile(gif, l_error); return 0; }
int iw = gif->SavedImages[0].ImageDesc.Width;
int ih = gif->SavedImages[0].ImageDesc.Height;
if(w) *w = iw;
if(h) *h = ih;
ARGB32 * data = (ARGB32 *)WASABI_API_MEMMGR->sysMalloc(iw * ih * sizeof(ARGB32));
ARGB32 * p = data;
ARGB32 * end = data + (iw * ih);
GifPixelType *line = gif->SavedImages[0].RasterBits;
if(gif->SavedImages[0].ImageDesc.Interlace)
{
// The way Interlaced image should be read - offsets and jumps...
const int InterlacedOffset[] = { 0, 4, 2, 1 };
const int InterlacedJumps[] = { 8, 8, 4, 2 };
for(int i = 0; i < 4; i++)
{
for(int j = InterlacedOffset[i]; j < ih; j += InterlacedJumps[i])
{
p = &data[j*iw];
for(int k = 0; k<iw; k++)
{
int px = *(line++);
if(px < map->ColorCount && (px != gif->SBackGroundColor || px == 0)) {
GifColorType& color = map->Colors[px];
*(p++) = 0xff000000 | color.Blue | (color.Green << 8) | (color.Red << 16);
} else
*(p++) = 0;
}
}
}
}
else
{
while(p < end) {
int px = *(line++);
if(px < map->ColorCount && (px != gif->SBackGroundColor || px == 0)) {
GifColorType& color = map->Colors[px];
*(p++) = 0xff000000 | color.Blue | (color.Green << 8) | (color.Red << 16);
} else
*(p++) = 0;
}
}
DGifCloseFile(gif, l_error);
return data;
}
#define CBCLASS GIFLoader
START_DISPATCH;
CB(ISMINE, isMine);
CB(MIMETYPE, mimeType);
CB(TESTDATA, testData);
CB(GETHEADERSIZE, getHeaderSize);
CB(GETDIMENSIONS, getDimensions);
CB(LOADIMAGE, loadImage);
CB(LOADIMAGEDATA, loadImageData);
END_DISPATCH;
#undef CBCLASS