diff options
Diffstat (limited to 'converter/other/giftopnm.c')
| -rw-r--r-- | converter/other/giftopnm.c | 214 |
1 files changed, 121 insertions, 93 deletions
diff --git a/converter/other/giftopnm.c b/converter/other/giftopnm.c index 239e5100..2e6ae1d9 100644 --- a/converter/other/giftopnm.c +++ b/converter/other/giftopnm.c @@ -39,10 +39,6 @@ #define MAX_LZW_BITS 12 -#define INTERLACE 0x40 -#define LOCALCOLORMAP 0x80 -#define BitSet(byte, bit) (((byte) & (bit)) == (bit)) - #if !defined(BYTE_ORDER) || !defined(LITTLE_ENDIAN) /* make sure (BYTE_ORDER == LITTLE_ENDIAN) is FALSE */ #define BYTE_ORDER 0 @@ -90,7 +86,7 @@ readFile(FILE * const ifP, -struct cmdlineInfo { +struct CmdlineInfo { /* All the information the user supplied in the command line, in a form easy for the program to use. */ @@ -111,7 +107,7 @@ struct cmdlineInfo { static void parseCommandLine(int argc, char ** argv, - struct cmdlineInfo * const cmdlineP) { + struct CmdlineInfo * const cmdlineP) { /*---------------------------------------------------------------------------- Note that the file spec array we return is stored in the storage that was passed to us as the argv array. @@ -240,13 +236,21 @@ typedef struct { -----------------------------------------------------------------------*/ -struct gifScreen { - unsigned int Width; - unsigned int Height; - GifColorMap ColorMap; - unsigned int ColorResolution; - unsigned int Background; - unsigned int AspectRatio; +struct GifScreen { + unsigned int width; + unsigned int height; + bool hasGlobalColorMap; + /* The stream has a global color map, to wit 'colorMap'. + (If the stream doesn't have a global color map, the individual + images must each have a local color map) + */ + GifColorMap colorMap; + /* The global color map for the stream. Meaningful only if + 'hasGlobalColorMap' is true. + */ + unsigned int colorResolution; + unsigned int background; + unsigned int aspectRatio; /* Aspect ratio of each pixel, times 64, minus 15. (i.e. 1 => 1:4). But Zero means 1:1. */ @@ -260,7 +264,7 @@ struct gifScreen { */ }; -struct gif89 { +struct Gif89 { bool haveTransColor; /* The GIF specifies a transparent background color */ unsigned int transparentIndex; @@ -278,7 +282,7 @@ struct gif89 { }; static void -initGif89(struct gif89 * const gif89P) { +initGif89(struct Gif89 * const gif89P) { gif89P->haveTransColor = false; gif89P->haveDelayTime = false; gif89P->haveInputFlag = false; @@ -297,7 +301,16 @@ readColorMap(FILE * const ifP, GifColorMap * const cmapP, bool * const hasGrayP, bool * const hasColorP) { +/*---------------------------------------------------------------------------- + Read a color map from a GIF stream, where the stream is on *ifP, + which is positioned to a color map, which is 'cmapSize' bytes long. + Return as *cmapP that color map. + + Furthermore, analyze that color map and return *hasGrayP == true iff it + contains any gray (black and white don't count) and *hasColorP == true iff + it contains anything that is not gray or black or white. +-----------------------------------------------------------------------------*/ unsigned int i; unsigned char rgb[3]; @@ -494,7 +507,7 @@ LM_to_uint(unsigned char const a, static void doGraphicControlExtension(FILE * const ifP, - struct gif89 * const gif89P) { + struct Gif89 * const gif89P) { bool eof; unsigned int length; @@ -531,7 +544,7 @@ doGraphicControlExtension(FILE * const ifP, static void doExtension(FILE * const ifP, unsigned char const label, - struct gif89 * const gif89P) { + struct Gif89 * const gif89P) { const char * str; @@ -566,7 +579,7 @@ doExtension(FILE * const ifP, -struct getCodeState { +struct GetCodeState { unsigned char buf[280]; /* This is the buffer through which we read the data from the stream. We must buffer it because we have to read whole data @@ -592,7 +605,7 @@ struct getCodeState { static void getAnotherBlock(FILE * const ifP, - struct getCodeState * const gsP, + struct GetCodeState * const gsP, const char ** const errorP) { unsigned int count; @@ -633,10 +646,10 @@ getAnotherBlock(FILE * const ifP, -static struct getCodeState getCodeState; +static struct GetCodeState getCodeState; static void -getCode_init(struct getCodeState * const getCodeStateP) { +getCode_init(struct GetCodeState * const getCodeStateP) { /* Fake a previous data block */ getCodeStateP->buf[0] = 0; @@ -688,7 +701,7 @@ bitsOfLeBuffer(const unsigned char * const buf, static void -getCode_get(struct getCodeState * const gsP, +getCode_get(struct GetCodeState * const gsP, FILE * const ifP, int const codeSize, bool * const eofP, @@ -752,7 +765,7 @@ getCode_get(struct getCodeState * const gsP, -struct stack { +struct Stack { /* Stack grows from low addresses to high addresses */ unsigned char * stack; /* malloc'ed array */ unsigned char * sp; /* stack pointer */ @@ -762,7 +775,7 @@ struct stack { static void -initStack(struct stack * const stackP, unsigned int const size) { +initStack(struct Stack * const stackP, unsigned int const size) { MALLOCARRAY(stackP->stack, size); if (stackP->stack == NULL) @@ -774,7 +787,7 @@ initStack(struct stack * const stackP, unsigned int const size) { static void -pushStack(struct stack * const stackP, unsigned char const value) { +pushStack(struct Stack * const stackP, unsigned char const value) { if (stackP->sp >= stackP->top) pm_error("stack overflow"); @@ -785,14 +798,14 @@ pushStack(struct stack * const stackP, unsigned char const value) { static bool -stackIsEmpty(const struct stack * const stackP) { +stackIsEmpty(const struct Stack * const stackP) { return stackP->sp == stackP->stack; } static unsigned char -popStack(struct stack * const stackP) { +popStack(struct Stack * const stackP) { if (stackP->sp <= stackP->stack) pm_error("stack underflow"); @@ -803,7 +816,7 @@ popStack(struct stack * const stackP) { static void -termStack(struct stack * const stackP) { +termStack(struct Stack * const stackP) { free(stackP->stack); stackP->stack = NULL; } @@ -851,8 +864,8 @@ termStack(struct stack * const stackP) { static int const maxLzwCodeCt = (1<<MAX_LZW_BITS); -struct decompressor { - struct stack stack; +struct Decompressor { + struct Stack stack; bool fresh; /* The stream is right after a clear code or at the very beginning */ unsigned int codeSize; @@ -891,7 +904,7 @@ struct decompressor { static void -resetDecompressor(struct decompressor * const decompP) { +resetDecompressor(struct Decompressor * const decompP) { decompP->codeSize = decompP->initCodeSize+1; decompP->maxCodeCt = 1 << decompP->codeSize; @@ -927,7 +940,7 @@ validateTransparentIndex(unsigned int const transparentIndex, static void -lzwInit(struct decompressor * const decompP, +lzwInit(struct Decompressor * const decompP, FILE * const ifP, int const initCodeSize, unsigned int const cmapSize, @@ -988,7 +1001,7 @@ lzwInit(struct decompressor * const decompP, static void -lzwAdjustForPBM(struct decompressor * const decompP, +lzwAdjustForPBM(struct Decompressor * const decompP, GifColorMap const cmap) { /*---------------------------------------------------------------------------- In the PBM case we use the table index value directly instead of looking up @@ -1006,7 +1019,7 @@ lzwAdjustForPBM(struct decompressor * const decompP, static void -lzwTerm(struct decompressor * const decompP) { +lzwTerm(struct Decompressor * const decompP) { termStack(&decompP->stack); } @@ -1014,7 +1027,7 @@ lzwTerm(struct decompressor * const decompP) { static void -pushWholeStringOnStack(struct decompressor * const decompP, +pushWholeStringOnStack(struct Decompressor * const decompP, unsigned int const code0) { /*---------------------------------------------------------------------------- Get the whole string that compression code 'code0' represents and push @@ -1038,7 +1051,7 @@ pushWholeStringOnStack(struct decompressor * const decompP, static void -expandCodeOntoStack(struct decompressor * const decompP, +expandCodeOntoStack(struct Decompressor * const decompP, unsigned int const incode, const char ** const errorP) { /*---------------------------------------------------------------------------- @@ -1113,8 +1126,8 @@ expandCodeOntoStack(struct decompressor * const decompP, static void -lzwReadByteFresh(struct getCodeState * const getCodeStateP, - struct decompressor * const decompP, +lzwReadByteFresh(struct GetCodeState * const getCodeStateP, + struct Decompressor * const decompP, bool * const endOfImageP, unsigned char * const dataReadP, const char ** const errorP) { @@ -1171,7 +1184,7 @@ lzwReadByteFresh(struct getCodeState * const getCodeStateP, static void -lzwReadByte(struct decompressor * const decompP, +lzwReadByte(struct Decompressor * const decompP, unsigned char * const dataReadP, bool * const endOfImageP, const char ** const errorP) { @@ -1398,7 +1411,7 @@ pnmFormat(bool const hasGray, static void -makePnmRow(struct decompressor * const decompP, +makePnmRow(struct Decompressor * const decompP, unsigned int const cols, unsigned int const rows, bool const fillWithZero, @@ -1447,7 +1460,7 @@ makePnmRow(struct decompressor * const decompP, static void -convertRaster(struct decompressor * const decompP, +convertRaster(struct Decompressor * const decompP, unsigned int const cols, unsigned int const rows, GifColorMap const cmap, @@ -1550,7 +1563,7 @@ convertRaster(struct decompressor * const decompP, static void -skipExtraneousData(struct decompressor * const decompP) { +skipExtraneousData(struct Decompressor * const decompP) { unsigned char byteRead; bool endOfImage; @@ -1638,7 +1651,7 @@ readImageData(FILE * const ifP, bool const tolerateBadInput) { unsigned char lzwMinCodeSize; - struct decompressor decomp; + struct Decompressor decomp; const char * error; readFile(ifP, &lzwMinCodeSize, sizeof(lzwMinCodeSize), &error); @@ -1697,12 +1710,14 @@ warnUserNotSquare(unsigned int const aspectRatio) { static void readGifHeader(FILE * const gifFileP, - struct gifScreen * const gifScreenP) { + struct GifScreen * const gifScreenP) { /*---------------------------------------------------------------------------- Read the GIF stream header off the file *gifFileP, which is present positioned to the beginning of a GIF stream. Return the info from it as *gifScreenP. -----------------------------------------------------------------------------*/ +#define GLOBALCOLORMAP 0x80 + unsigned char buf[16]; char version[4]; unsigned int cmapSize; @@ -1729,44 +1744,46 @@ readGifHeader(FILE * const gifFileP, if (error) pm_error("Failed to read screen descriptor. %s", error); - gifScreenP->Width = LM_to_uint(buf[0],buf[1]); - gifScreenP->Height = LM_to_uint(buf[2],buf[3]); + gifScreenP->width = LM_to_uint(buf[0],buf[1]); + gifScreenP->height = LM_to_uint(buf[2],buf[3]); cmapSize = 1 << ((buf[4] & 0x07) + 1); - gifScreenP->ColorResolution = (buf[4] & 0x70 >> 3) + 1; - gifScreenP->Background = buf[5]; - gifScreenP->AspectRatio = buf[6]; + gifScreenP->colorResolution = (buf[4] & 0x70 >> 3) + 1; + gifScreenP->background = buf[5]; + gifScreenP->aspectRatio = buf[6]; if (verbose) { - pm_message("GIF Width = %d GIF Height = %d " - "Pixel aspect ratio = %d (%f:1)", - gifScreenP->Width, gifScreenP->Height, - gifScreenP->AspectRatio, - gifScreenP->AspectRatio == 0 ? - 1 : (gifScreenP->AspectRatio + 15) / 64.0); - pm_message("Colors = %d Color Resolution = %d", - cmapSize, gifScreenP->ColorResolution); + pm_message("GIF Width = %u GIF Height = %u " + "Pixel aspect ratio = %u (%f:1)", + gifScreenP->width, gifScreenP->height, + gifScreenP->aspectRatio, + gifScreenP->aspectRatio == 0 ? + 1 : (gifScreenP->aspectRatio + 15) / 64.0); + pm_message("Global color count = %u Color Resolution = %u", + cmapSize, gifScreenP->colorResolution); } - if (BitSet(buf[4], LOCALCOLORMAP)) { /* Global Colormap */ - readColorMap(gifFileP, cmapSize, &gifScreenP->ColorMap, + if (buf[4] & GLOBALCOLORMAP) { + gifScreenP->hasGlobalColorMap = true; + readColorMap(gifFileP, cmapSize, &gifScreenP->colorMap, &gifScreenP->hasGray, &gifScreenP->hasColor); if (verbose) { - pm_message("Color map %s grays, %s colors", + pm_message("Global color map %s grays, %s colors", gifScreenP->hasGray ? "contains" : "doesn't contain", gifScreenP->hasColor ? "contains" : "doesn't contain"); } - } else { - gifScreenP->ColorMap.size = 0; - } + } else + gifScreenP->hasGlobalColorMap = false; - if (gifScreenP->AspectRatio != 0 && gifScreenP->AspectRatio != 49) - warnUserNotSquare(gifScreenP->AspectRatio); + if (gifScreenP->aspectRatio != 0 && gifScreenP->aspectRatio != 49) + warnUserNotSquare(gifScreenP->aspectRatio); + +#undef GLOBALCOLORMAP } static void readExtensions(FILE* const ifP, - struct gif89 * const gif89P, + struct Gif89 * const gif89P, bool * const eodP, const char ** const errorP) { /*---------------------------------------------------------------------------- @@ -1832,7 +1849,13 @@ struct GifImageHeader { /*---------------------------------------------------------------------------- Information in the header (first 9 bytes) of a GIF image. -----------------------------------------------------------------------------*/ - bool useGlobalColormap; + bool hasLocalColormap; + /* The image has its own color map. Its size is 'localColorMapSize' */ + /* (If an image does not have its own color map, the image uses the + global color map for the GIF stream) + */ + unsigned int localColorMapSize; + /* Meaningful only if 'hasLocalColormap' is true. */ /* Position of the image (max 65535) */ unsigned int lpos; @@ -1841,7 +1864,7 @@ struct GifImageHeader { /* Dimensions of the image (max 65535) */ unsigned int cols; unsigned int rows; - unsigned int localColorMapSize; + bool interlaced; }; @@ -1858,11 +1881,11 @@ reportImageHeader(struct GifImageHeader const imageHeader) { pm_message(" Image left position: %u top position: %u", imageHeader.lpos, imageHeader.tpos); - if (imageHeader.useGlobalColormap) - pm_message(" Uses global colormap"); - else + if (imageHeader.hasLocalColormap) pm_message(" Uses local colormap of %u colors", imageHeader.localColorMapSize); + else + pm_message(" Uses global colormap"); } @@ -1871,6 +1894,9 @@ static void readImageHeader(FILE * const ifP, struct GifImageHeader * const imageHeaderP) { +#define LOCALCOLORMAP 0x80 +#define INTERLACE 0x40 + unsigned char buf[16]; const char * error; @@ -1878,34 +1904,37 @@ readImageHeader(FILE * const ifP, if (error) pm_error("couldn't read left/top/width/height. %s", error); - imageHeaderP->useGlobalColormap = ! BitSet(buf[8], LOCALCOLORMAP); + imageHeaderP->hasLocalColormap = !!(buf[8] & LOCALCOLORMAP); imageHeaderP->localColorMapSize = 1u << ((buf[8] & 0x07) + 1); imageHeaderP->lpos = LM_to_uint(buf[0], buf[1]); imageHeaderP->tpos = LM_to_uint(buf[2], buf[3]); imageHeaderP->cols = LM_to_uint(buf[4], buf[5]); imageHeaderP->rows = LM_to_uint(buf[6], buf[7]); - imageHeaderP->interlaced = !!BitSet(buf[8], INTERLACE); + imageHeaderP->interlaced = !!(buf[8] & INTERLACE); if (verbose) reportImageHeader(*imageHeaderP); + +#undef INTERLACE +#undef LOCALCOLORMAP } static void validateWithinGlobalScreen(struct GifImageHeader const imageHeader, - struct gifScreen const gifScreen) { + struct GifScreen const gifScreen) { unsigned long int const rpos = imageHeader.lpos + imageHeader.cols; unsigned long int const bpos = imageHeader.tpos + imageHeader.rows; - if (rpos > gifScreen.Width) + if (rpos > gifScreen.width) pm_error("Image right end (%lu) is outside global screen: %u x %u", - rpos, gifScreen.Width, gifScreen.Height); - if (bpos > gifScreen.Height) + rpos, gifScreen.width, gifScreen.height); + if (bpos > gifScreen.height) pm_error("Image bottom end (%lu) is outside global screen: " "%u x %u", - bpos, gifScreen.Width, gifScreen.Height); + bpos, gifScreen.width, gifScreen.height); } @@ -1930,8 +1959,8 @@ convertImage(FILE * const ifP, bool const skipIt, FILE * const imageoutFileP, FILE * const alphafileP, - struct gifScreen const gifScreen, - struct gif89 const gif89, + struct GifScreen const gifScreen, + struct Gif89 const gif89, bool const tolerateBadInput) { /*---------------------------------------------------------------------------- Read a single GIF image from the current position of file 'ifP'. @@ -1949,19 +1978,18 @@ convertImage(FILE * const ifP, validateWithinGlobalScreen(imageHeader, gifScreen); - if (imageHeader.useGlobalColormap) { - if (gifScreen.ColorMap.size == 0) { - pm_error("Invalid GIF: " - "Image has no local color map and stream has no global " - "color map either."); - } - currentColorMapP = &gifScreen.ColorMap; - hasGray = gifScreen.hasGray; - hasColor = gifScreen.hasColor; - } else { + if (imageHeader.hasLocalColormap) { readColorMap(ifP, imageHeader.localColorMapSize, &localColorMap, &hasGray, &hasColor); currentColorMapP = &localColorMap; + } else if (gifScreen.hasGlobalColorMap) { + currentColorMapP = &gifScreen.colorMap; + hasGray = gifScreen.hasGray; + hasColor = gifScreen.hasColor; + } else { + pm_error("Invalid GIF: " + "Image has no local color map and stream has no global " + "color map either."); } if (!skipIt) { @@ -2027,8 +2055,8 @@ convertImages(FILE * const ifP, /* Sequence within GIF stream of image we are currently processing. First is 0. */ - struct gifScreen gifScreen; - struct gif89 gif89; + struct GifScreen gifScreen; + struct Gif89 gif89; bool eod; /* We've read through the GIF terminator character */ @@ -2072,7 +2100,7 @@ convertImages(FILE * const ifP, int main(int argc, char **argv) { - struct cmdlineInfo cmdline; + struct CmdlineInfo cmdline; FILE * ifP; FILE * alphaFileP; FILE * imageOutFileP; |