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|
/*
* This file is subject to the terms of the GFX License. If a copy of
* the license was not distributed with this file, you can obtain one at:
*
* http://ugfx.org/license.html
*/
#include "../../gfx.h"
#if GFX_USE_GDISP && GDISP_NEED_IMAGE && GDISP_NEED_IMAGE_GIF
#include "gdisp_image_support.h"
// We need a special error to indicate the end of file (which may not actually be an error)
#define GDISP_IMAGE_GIF_EOF ((gdispImageError)-1)
#define GDISP_IMAGE_GIF_LOOP ((gdispImageError)-2)
#define GIF_MAX_CODE_BITS 12
#define GIF_CODE_MAX ((1<<GIF_MAX_CODE_BITS)-1) // Maximum legal code value
#define GIF_CODE_FLUSH (GIF_CODE_MAX+1) // Illegal code to signal flush
#define GIF_CODE_FIRST (GIF_CODE_MAX+2) // Illegal code to signal first
#define GIF_CODE_NONE (GIF_CODE_MAX+3) // Illegal code to signal empty
// Convert bits to masks for that number of bits
static const uint16_t GifBitMask[] = {
0x0000, 0x0001, 0x0003, 0x0007,
0x000f, 0x001f, 0x003f, 0x007f,
0x00ff, 0x01ff, 0x03ff, 0x07ff,
0x0fff
};
// Structure for decoding a single frame
typedef struct gifimgdecode {
uint8_t blocksz; // The size of the block currently being processed
uint8_t maxpixel; // The maximum allowed pixel value
uint8_t bitsperpixel;
uint8_t bitspercode;
uint8_t shiftbits;
uint16_t maxcodesz;
uint16_t stackcnt; // The number of items on the stack
uint16_t code_clear;
uint16_t code_eof;
uint16_t code_max;
uint16_t code_last;
uint32_t shiftdata;
color_t * palette;
uint8_t buf[GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE]; // Buffer for decoded pixels
uint16_t prefix[1<<GIF_MAX_CODE_BITS]; // The LZW table
uint8_t suffix[1<<GIF_MAX_CODE_BITS]; // So we can trace the codes
uint8_t stack[1<<GIF_MAX_CODE_BITS]; // Decoded pixels might be stacked here
} gifimgdecode;
// The data on a single frame
typedef struct gifimgframe {
coord_t x, y; // position relative to full image
coord_t width, height; // size of frame
uint16_t delay; // delay after processing
uint8_t flags; // Local flags
#define GIFL_TRANSPARENT 0x01 // There exists a transparent color
#define GIFL_DISPOSECLEAR 0x02 // Dispose this frame by clearing
#define GIFL_DISPOSEREST 0x04 // Dispose this frame by restoring
#define GIFL_INTERLACE 0x08 // Current frame is interlaced
uint8_t paltrans; // Transparency
uint16_t palsize; // Local palette size
size_t posstart; // The file position of the start of the image
size_t pospal; // The file position of the palette
size_t posimg; // The file position of the image bits
size_t posend; // The file position of the end of the frame
} gifimgframe;
// The data for a cache
typedef struct gifimgcache {
gifimgframe frame;
color_t * palette; // Local palette
uint8_t * imagebits; // Image bits - only saved when caching
struct gifimgcache *next; // Next cached frame
} gifimgcache;
// The data for a dispose area
typedef struct gifimgdispose {
uint8_t flags; // Frame flags
uint8_t paltrans; // Transparency
coord_t x, y; // position relative to full image
coord_t width, height; // size of dispose area
} gifimgdispose;
typedef struct gdispImagePrivate_GIF {
uint8_t flags; // Flags (global)
#define GIF_LOOP 0x01 // Loop back to first frame
#define GIF_LOOPFOREVER 0x02 // Looping is forever
uint8_t bgcolor; // Background Color (global)
uint16_t loops; // Remaining frame loops (if animated)
uint16_t palsize; // Global palette size (global)
pixel_t *palette; // Global palette (global)
size_t frame0pos; // The position of the first frame
gifimgcache * cache; // The list of cached frames
gifimgcache * curcache; // The cache of the current frame (if created)
gifimgdecode * decode; // The decode data for the decode in progress
gifimgframe frame;
gifimgdispose dispose;
pixel_t buf[GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE]; // Buffer for reading and blitting
} gdispImagePrivate_GIF;
/**
* Get ready for decoding a frame.
*
* Pre: Frame info has been read.
*/
static gdispImageError startDecodeGif(gdispImage *img) {
gdispImagePrivate_GIF * priv;
gifimgdecode * decode;
uint16_t cnt;
priv = (gdispImagePrivate_GIF *)img->priv;
// We need the decode ram, and possibly a palette
if (!(decode = (gifimgdecode *)gdispImageAlloc(img, sizeof(gifimgdecode)+priv->frame.palsize*sizeof(color_t))))
return GDISP_IMAGE_ERR_NOMEMORY;
// We currently have not read any image data block
decode->blocksz = 0;
// Set the palette
if (priv->frame.palsize) {
// Local palette
decode->maxpixel = priv->frame.palsize-1;
decode->palette = (color_t *)(decode+1);
gfileSetPos(img->f, priv->frame.pospal);
for(cnt = 0; cnt < priv->frame.palsize; cnt++) {
if (gfileRead(img->f, &decode->buf, 3) != 3)
goto baddatacleanup;
decode->palette[cnt] = RGB2COLOR(decode->buf[0], decode->buf[1], decode->buf[2]);
}
} else if (priv->palette) {
// Global palette
decode->maxpixel = priv->palsize-1;
decode->palette = priv->palette;
} else {
// Oops - we must have a palette
goto baddatacleanup;
}
// Get the initial lzw code size and values
gfileSetPos(img->f, priv->frame.posimg);
if (gfileRead(img->f, &decode->bitsperpixel, 1) != 1 || decode->bitsperpixel >= GIF_MAX_CODE_BITS)
goto baddatacleanup;
decode->code_clear = 1 << decode->bitsperpixel;
decode->code_eof = decode->code_clear + 1;
decode->code_max = decode->code_clear + 2;
decode->code_last = GIF_CODE_NONE;
decode->bitspercode = decode->bitsperpixel+1;
decode->maxcodesz = 1 << decode->bitspercode;
decode->shiftbits = 0;
decode->shiftdata = 0;
decode->stackcnt = 0;
for(cnt = 0; cnt <= GIF_CODE_MAX; cnt++)
decode->prefix[cnt] = GIF_CODE_NONE;
// All ready to go
priv->decode = decode;
return GDISP_IMAGE_ERR_OK;
baddatacleanup:
gdispImageFree(img, decode, sizeof(gifimgdecode)+priv->frame.palsize*sizeof(color_t));
return GDISP_IMAGE_ERR_BADDATA;
}
/**
* Stop decoding a frame.
*
* Pre: Frame info has been read.
*/
static void stopDecodeGif(gdispImage *img) {
gdispImagePrivate_GIF * priv;
priv = (gdispImagePrivate_GIF *)img->priv;
// Free the decode data
if (priv->decode) {
gdispImageFree(img, (void *)priv->decode, sizeof(gifimgdecode)+priv->frame.palsize*sizeof(color_t));
priv->decode = 0;
}
}
static uint16_t getPrefixGif(gifimgdecode *decode, uint16_t code) {
uint16_t i;
for(i=0; code > decode->code_clear && i <= GIF_CODE_MAX; i++, code = decode->prefix[code]) {
if (code > GIF_CODE_MAX)
return GIF_CODE_NONE;
}
return code;
}
/**
* Decode some pixels from a frame.
*
* Pre: We are ready for decoding.
*
* Return: The number of pixels decoded 0 .. GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE-1. 0 means EOF
*
* Note: The resulting pixels are stored in decode->buf
*/
static uint16_t getBytesGif(gdispImage *img) {
gdispImagePrivate_GIF * priv;
gifimgdecode * decode;
uint16_t cnt;
uint16_t code, prefix;
uint8_t bdata;
priv = (gdispImagePrivate_GIF *)img->priv;
decode = priv->decode;
cnt = 0;
// At EOF
if (decode->code_last == decode->code_eof)
return 0;
while(cnt < sizeof(decode->buf)) {
// Use the stack up first
if (decode->stackcnt > 0) {
decode->buf[cnt++] = decode->stack[--decode->stackcnt];
continue;
}
// Get another code - a code is made up of decode->bitspercode bits.
while (decode->shiftbits < decode->bitspercode) {
// Get a byte - we may have to start a new data block
if ((!decode->blocksz && (gfileRead(img->f, &decode->blocksz, 1) != 1 || !decode->blocksz))
|| gfileRead(img->f, &bdata, 1) != 1) {
// Pretend we got the EOF code - some encoders seem to just end the file
decode->code_last = decode->code_eof;
return cnt;
}
decode->blocksz--;
decode->shiftdata |= ((unsigned long)bdata) << decode->shiftbits;
decode->shiftbits += 8;
}
code = decode->shiftdata & GifBitMask[decode->bitspercode];
decode->shiftdata >>= decode->bitspercode;
decode->shiftbits -= decode->bitspercode;
/**
* If code cannot fit into bitspercode bits we must raise its size.
* Note that codes above GIF_CODE_MAX are used for special signaling.
* If we're using GIF_MAX_CODE_BITS bits already and we're at the max code, just
* keep using the table as it is, don't increment decode->bitspercode.
*/
if (decode->code_max < GIF_CODE_MAX + 2 && ++decode->code_max > decode->maxcodesz && decode->bitspercode < GIF_MAX_CODE_BITS) {
decode->maxcodesz <<= 1;
decode->bitspercode++;
}
// EOF - the appropriate way to stop decoding
if (code == decode->code_eof) {
// Skip to the end of the data blocks
do {
gfileSetPos(img->f, gfileGetPos(img->f)+decode->blocksz);
} while (gfileRead(img->f, &decode->blocksz, 1) == 1 && decode->blocksz);
// Mark the end
decode->code_last = decode->code_eof;
break;
}
if (code == decode->code_clear) {
// Start again
for(prefix = 0; prefix <= GIF_CODE_MAX; prefix++)
decode->prefix[prefix] = GIF_CODE_NONE;
decode->code_max = decode->code_eof + 1;
decode->bitspercode = decode->bitsperpixel + 1;
decode->maxcodesz = 1 << decode->bitspercode;
decode->code_last = GIF_CODE_NONE;
continue;
}
if (code < decode->code_clear) {
// Simple unencoded pixel - add it
decode->buf[cnt++] = code;
} else {
/**
* Its a LZW code - trace the linked list until the prefix is a
* valid pixel while pushing the suffix pixels on the stack.
* If done, pop the stack in reverse order adding the pixels
*/
if (decode->prefix[code] != GIF_CODE_NONE)
prefix = code;
/**
* Only allowed if the code equals the partial code.
* In that case code = XXXCode, CrntCode or the
* prefix code is last code and the suffix char is
* exactly the prefix of last code!
*/
else if (code == decode->code_max - 2 && decode->stackcnt < sizeof(decode->stack)) {
prefix = decode->code_last;
decode->suffix[decode->code_max - 2] = decode->stack[decode->stackcnt++] = getPrefixGif(decode, decode->code_last);
} else
return 0;
/**
* If the image is OK we should not get a GIF_CODE_NONE while tracing.
* To prevent looping with a bad image we use StackPtr as loop counter
* and stop before overflowing Stack[].
*/
while (decode->stackcnt < sizeof(decode->stack) && prefix > decode->code_clear && prefix <= GIF_CODE_MAX) {
decode->stack[decode->stackcnt++] = decode->suffix[prefix];
prefix = decode->prefix[prefix];
}
if (decode->stackcnt >= sizeof(decode->stack) || prefix > GIF_CODE_MAX)
return 0;
/* Push the last character on stack: */
decode->stack[decode->stackcnt++] = prefix;
}
if (decode->code_last != GIF_CODE_NONE && decode->prefix[decode->code_max - 2] == GIF_CODE_NONE) {
decode->prefix[decode->code_max - 2] = decode->code_last;
/* Only allowed if code is exactly the running code:
* In that case code = XXXCode, CrntCode or the
* prefix code is last code and the suffix char is
* exactly the prefix of last code! */
decode->suffix[decode->code_max - 2] = getPrefixGif(decode, code == decode->code_max - 2 ? decode->code_last : code);
}
decode->code_last = code;
}
return cnt;
}
/**
* Read the info on a frame.
*
* Pre: The file position is at the start of the frame.
*/
static gdispImageError initFrameGif(gdispImage *img) {
gdispImagePrivate_GIF * priv;
gifimgcache * cache;
uint8_t blocktype;
uint8_t blocksz;
priv = (gdispImagePrivate_GIF *)img->priv;
// Save the dispose info from the existing frame
priv->dispose.flags = priv->frame.flags;
priv->dispose.paltrans = priv->frame.paltrans;
priv->dispose.x = priv->frame.x;
priv->dispose.y = priv->frame.y;
priv->dispose.width = priv->frame.width;
priv->dispose.height = priv->frame.height;
// Check for a cached version of this image
for(cache=priv->cache; cache && cache->frame.posstart <= (size_t)gfileGetPos(img->f); cache=cache->next) {
if (cache->frame.posstart == (size_t)gfileGetPos(img->f)) {
priv->frame = cache->frame;
priv->curcache = cache;
return GDISP_IMAGE_ERR_OK;
}
}
// Get ready for a new image
priv->curcache = 0;
priv->frame.posstart = gfileGetPos(img->f);
priv->frame.flags = 0;
priv->frame.delay = 0;
priv->frame.palsize = 0;
// Process blocks until we reach the image descriptor
while(1) {
if (gfileRead(img->f, &blocktype, 1) != 1)
return GDISP_IMAGE_ERR_BADDATA;
switch(blocktype) {
case 0x2C: //',' - IMAGE_DESC_RECORD_TYPE;
// Read the Image Descriptor
if (gfileRead(img->f, priv->buf, 9) != 9)
return GDISP_IMAGE_ERR_BADDATA;
priv->frame.x = gdispImageGetAlignedLE16(priv->buf, 0);
priv->frame.y = gdispImageGetAlignedLE16(priv->buf, 2);
priv->frame.width = gdispImageGetAlignedLE16(priv->buf, 4);
priv->frame.height = gdispImageGetAlignedLE16(priv->buf, 6);
if (((uint8_t *)priv->buf)[8] & 0x80) // Local color table?
priv->frame.palsize = 2 << (((uint8_t *)priv->buf)[8] & 0x07);
if (((uint8_t *)priv->buf)[8] & 0x40) // Interlaced?
priv->frame.flags |= GIFL_INTERLACE;
// We are ready to go for the actual palette read and image decode
priv->frame.pospal = gfileGetPos(img->f);
priv->frame.posimg = priv->frame.pospal+priv->frame.palsize*3;
priv->frame.posend = 0;
// Mark this as an animated image if more than 1 frame.
if (priv->frame.posstart != priv->frame0pos)
img->flags |= GDISP_IMAGE_FLG_ANIMATED;
return GDISP_IMAGE_ERR_OK;
case 0x21: //'!' - EXTENSION_RECORD_TYPE;
// Read the extension type
if (gfileRead(img->f, &blocktype, 1) != 1)
return GDISP_IMAGE_ERR_BADDATA;
switch(blocktype) {
case 0xF9: // EXTENSION - Graphics Control Block
// Read the GCB
if (gfileRead(img->f, priv->buf, 6) != 6)
return GDISP_IMAGE_ERR_BADDATA;
// Check we have read a 4 byte data block and a data block terminator (0)
if (((uint8_t *)priv->buf)[0] != 4 || ((uint8_t *)priv->buf)[5] != 0)
return GDISP_IMAGE_ERR_BADDATA;
// Process the flags
switch(((uint8_t *)priv->buf)[1] & 0x1C) {
case 0x00: case 0x04: break; // Dispose = do nothing
case 0x08: priv->frame.flags |= GIFL_DISPOSECLEAR; break; // Dispose = clear
case 0x0C: case 0x10: priv->frame.flags |= GIFL_DISPOSEREST; break; // Dispose = restore. Value 0x10 is a hack for bad encoders
default: return GDISP_IMAGE_ERR_UNSUPPORTED;
}
if (((uint8_t *)priv->buf)[1] & 0x01) {
priv->frame.flags |= GIFL_TRANSPARENT;
img->flags |= GDISP_IMAGE_FLG_TRANSPARENT; // We set this but never clear it
}
if (((uint8_t *)priv->buf)[1] & 0x02) // Wait for user input?
img->flags |= GDISP_IMAGE_FLG_MULTIPAGE;
else
img->flags &= ~GDISP_IMAGE_FLG_MULTIPAGE;
// Process frame delay and the transparent color (if any)
priv->frame.delay = gdispImageGetAlignedLE16(priv->buf, 2);
priv->frame.paltrans = ((uint8_t *)priv->buf)[4];
break;
case 0xFF: // EXTENSION - Application
// We only handle this for the special Netscape loop counter for animation
if (priv->flags & GIF_LOOP)
goto skipdatablocks;
// Read the Application header
if (gfileRead(img->f, priv->buf, 16) != 16)
return GDISP_IMAGE_ERR_BADDATA;
// Check we have read a 11 byte data block
if (((uint8_t *)priv->buf)[0] != 11 && ((uint8_t *)priv->buf)[12] != 3)
return GDISP_IMAGE_ERR_BADDATA;
// Check the vendor
if (((uint8_t *)priv->buf)[1] == 'N' && ((uint8_t *)priv->buf)[2] == 'E' && ((uint8_t *)priv->buf)[3] == 'T'
&& ((uint8_t *)priv->buf)[4] == 'S' && ((uint8_t *)priv->buf)[5] == 'C' && ((uint8_t *)priv->buf)[6] == 'A'
&& ((uint8_t *)priv->buf)[7] == 'P' && ((uint8_t *)priv->buf)[8] == 'E' && ((uint8_t *)priv->buf)[9] == '2'
&& ((uint8_t *)priv->buf)[10] == '.' && ((uint8_t *)priv->buf)[11] == '0') {
if (((uint8_t *)priv->buf)[13] == 1) {
priv->loops = gdispImageGetAlignedLE16(priv->buf, 14);
priv->flags |= GIF_LOOP;
if (!priv->loops)
priv->flags |= GIF_LOOPFOREVER;
}
}
goto skipdatablocks;
case 0x01: // EXTENSION - Plain Text (Graphics Rendering)
case 0xFE: // EXTENSION - Comment
default:
// 0x00-0x7F (0-127) are the Graphic Rendering blocks
if (blocktype <= 0x7F)
return GDISP_IMAGE_ERR_UNSUPPORTED;
// 0x80-0xF9 (128-249) are the Control blocks
// 0xFA-0xFF (250-255) are the Special Purpose blocks
// We don't understand this extension - just skip it by skipping data blocks
skipdatablocks:
while(1) {
if (gfileRead(img->f, &blocksz, 1) != 1)
return GDISP_IMAGE_ERR_BADDATA;
if (!blocksz)
break;
gfileSetPos(img->f, gfileGetPos(img->f) + blocksz);
}
break;
}
break;
case 0x3B: //';' - TERMINATE_RECORD_TYPE;
// Are we an looping animation
if (!(priv->flags & GIF_LOOP))
return GDISP_IMAGE_GIF_EOF;
if (!(priv->flags & GIF_LOOPFOREVER)) {
if (!priv->loops)
return GDISP_IMAGE_GIF_EOF;
priv->loops--;
}
// Seek back to frame0
gfileSetPos(img->f, priv->frame0pos);
return GDISP_IMAGE_GIF_LOOP;
default: // UNDEFINED_RECORD_TYPE;
return GDISP_IMAGE_ERR_UNSUPPORTED;
}
}
}
void gdispImageClose_GIF(gdispImage *img) {
gdispImagePrivate_GIF * priv;
gifimgcache * cache;
gifimgcache * ncache;
priv = (gdispImagePrivate_GIF *)img->priv;
if (priv) {
// Free any stored frames
cache = priv->cache;
while(cache) {
ncache = cache->next;
gdispImageFree(img, (void *)cache, sizeof(gifimgcache)+cache->frame.width*cache->frame.height+cache->frame.palsize*sizeof(color_t));
cache = ncache;
}
if (priv->palette)
gdispImageFree(img, (void *)priv->palette, priv->palsize*sizeof(color_t));
gdispImageFree(img, (void *)priv, sizeof(gdispImagePrivate_GIF));
img->priv = 0;
}
}
gdispImageError gdispImageOpen_GIF(gdispImage *img) {
gdispImagePrivate_GIF *priv;
uint8_t hdr[6];
uint16_t aword;
/* Read the file identifier */
if (gfileRead(img->f, hdr, 6) != 6)
return GDISP_IMAGE_ERR_BADFORMAT; // It can't be us
/* Process the GIFFILEHEADER structure */
if (hdr[0] != 'G' || hdr[1] != 'I' || hdr[2] != 'F'
|| hdr[3] != '8' || (hdr[4] != '7' && hdr[4] != '9') || hdr[5] != 'a')
return GDISP_IMAGE_ERR_BADFORMAT; // It can't be us
/* We know we are a GIF format image */
img->flags = 0;
/* Allocate our private area */
if (!(img->priv = gdispImageAlloc(img, sizeof(gdispImagePrivate_GIF))))
return GDISP_IMAGE_ERR_NOMEMORY;
/* Initialise the essential bits in the private area */
priv = (gdispImagePrivate_GIF *)img->priv;
priv->flags = 0;
priv->palsize = 0;
priv->palette = 0;
priv->frame.flags = 0;
priv->cache = 0;
priv->curcache = 0;
priv->decode = 0;
/* Process the Screen Descriptor structure */
// Read the screen descriptor
if (gfileRead(img->f, priv->buf, 7) != 7)
goto baddatacleanup;
// Get the width
img->width = gdispImageGetAlignedLE16(priv->buf, 0);
// Get the height
img->height = gdispImageGetAlignedLE16(priv->buf, 2);
if (((uint8_t *)priv->buf)[4] & 0x80) {
// Global color table
priv->palsize = 2 << (((uint8_t *)priv->buf)[4] & 0x07);
// Allocate the global palette
if (!(priv->palette = (color_t *)gdispImageAlloc(img, priv->palsize*sizeof(color_t))))
goto nomemcleanup;
// Read the global palette
for(aword = 0; aword < priv->palsize; aword++) {
if (gfileRead(img->f, &priv->buf, 3) != 3)
goto baddatacleanup;
priv->palette[aword] = RGB2COLOR(((uint8_t *)priv->buf)[0], ((uint8_t *)priv->buf)[1], ((uint8_t *)priv->buf)[2]);
}
}
priv->bgcolor = ((uint8_t *)priv->buf)[5];
// Save the fram0pos
priv->frame0pos = gfileGetPos(img->f);
// Read the first frame descriptor
switch(initFrameGif(img)) {
case GDISP_IMAGE_ERR_OK: // Everything OK
img->type = GDISP_IMAGE_TYPE_GIF;
return GDISP_IMAGE_ERR_OK;
case GDISP_IMAGE_ERR_UNSUPPORTED: // Unsupported
gdispImageClose_GIF(img); // Clean up the private data area
return GDISP_IMAGE_ERR_UNSUPPORTED;
case GDISP_IMAGE_ERR_NOMEMORY: // Out of Memory
nomemcleanup:
gdispImageClose_GIF(img); // Clean up the private data area
return GDISP_IMAGE_ERR_NOMEMORY;
case GDISP_IMAGE_GIF_EOF: // We should have a frame but we don't seem to
case GDISP_IMAGE_GIF_LOOP: // We should have a frame but we don't seem to
case GDISP_IMAGE_ERR_BADDATA: // Oops - something wrong with the data
default:
baddatacleanup:
gdispImageClose_GIF(img); // Clean up the private data area
return GDISP_IMAGE_ERR_BADDATA;
}
}
gdispImageError gdispImageCache_GIF(gdispImage *img) {
gdispImagePrivate_GIF * priv;
gifimgcache * cache;
gifimgdecode * decode;
uint8_t * p;
uint8_t * q;
coord_t mx, my;
uint16_t cnt;
/* If we are already cached - just return OK */
priv = (gdispImagePrivate_GIF *)img->priv;
if (priv->curcache)
return GDISP_IMAGE_ERR_OK;
/* We need to allocate the frame, the palette and bits for the image */
if (!(cache = (gifimgcache *)gdispImageAlloc(img, sizeof(gifimgcache) + priv->frame.palsize*sizeof(color_t) + priv->frame.width*priv->frame.height)))
return GDISP_IMAGE_ERR_NOMEMORY;
/* Initialise the cache */
decode = 0;
cache->frame = priv->frame;
cache->imagebits = (uint8_t *)(cache+1) + cache->frame.palsize*sizeof(color_t);
cache->next = 0;
/* Start the decode */
switch(startDecodeGif(img)) {
case GDISP_IMAGE_ERR_OK: break;
case GDISP_IMAGE_ERR_NOMEMORY: goto nomemcleanup;
case GDISP_IMAGE_ERR_BADDATA:
default: goto baddatacleanup;
}
decode = priv->decode;
// Save the palette
if (cache->frame.palsize) {
cache->palette = (color_t *)(cache+1);
/* Copy the local palette into the cache */
for(cnt = 0; cnt < cache->frame.palsize; cnt++)
cache->palette[cnt] = decode->palette[cnt];
} else
cache->palette = priv->palette;
// Check for interlacing
cnt = 0;
q = 0;
if (cache->frame.flags & GIFL_INTERLACE) {
// Every 8th row starting at row 0
for(p=cache->imagebits, my=0; my < cache->frame.height; my+=8, p += cache->frame.width*7) {
for(mx=0; mx < cache->frame.width; mx++) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
while(cnt < sizeof(decode->buf))
decode->buf[cnt++] = (cache->frame.flags & GIFL_TRANSPARENT) ? cache->frame.paltrans : 0;
}
q = decode->buf;
}
*p++ = *q++;
cnt--;
}
}
// Every 8th row starting at row 4
for(p=cache->imagebits+cache->frame.width*4, my=4; my < cache->frame.height; my+=8, p += cache->frame.width*7) {
for(mx=0; mx < cache->frame.width; mx++) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
while(cnt < sizeof(decode->buf))
decode->buf[cnt++] = (cache->frame.flags & GIFL_TRANSPARENT) ? cache->frame.paltrans : 0;
}
q = decode->buf;
}
*p++ = *q++;
cnt--;
}
}
// Every 4th row starting at row 2
for(p=cache->imagebits+cache->frame.width*2, my=2; my < cache->frame.height; my+=4, p += cache->frame.width*3) {
for(mx=0; mx < cache->frame.width; mx++) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
while(cnt < sizeof(decode->buf))
decode->buf[cnt++] = (cache->frame.flags & GIFL_TRANSPARENT) ? cache->frame.paltrans : 0;
}
q = decode->buf;
}
*p++ = *q++;
cnt--;
}
}
// Every 2nd row starting at row 1
for(p=cache->imagebits+cache->frame.width, my=1; my < cache->frame.height; my+=2, p += cache->frame.width) {
for(mx=0; mx < cache->frame.width; mx++) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
while(cnt < sizeof(decode->buf))
decode->buf[cnt++] = (cache->frame.flags & GIFL_TRANSPARENT) ? cache->frame.paltrans : 0;
}
q = decode->buf;
}
*p++ = *q++;
cnt--;
}
}
} else {
// Every row in sequence
p=cache->imagebits;
for(my=0; my < cache->frame.height; my++) {
for(mx=0; mx < cache->frame.width; mx++) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
while(cnt < sizeof(decode->buf))
decode->buf[cnt++] = (cache->frame.flags & GIFL_TRANSPARENT) ? cache->frame.paltrans : 0;
}
q = decode->buf;
}
*p++ = *q++;
cnt--;
}
}
}
// We could be pedantic here but extra bytes won't hurt us
while(getBytesGif(img));
priv->frame.posend = cache->frame.posend = gfileGetPos(img->f);
// Save everything
priv->curcache = cache;
if (!priv->cache)
priv->cache = cache;
else if (priv->cache->frame.posstart > cache->frame.posstart) {
cache->next = priv->cache;
priv->cache = cache;
} else {
gifimgcache *pc;
for(pc = priv->cache; pc; pc = pc->next) {
if (!pc->next || pc->next->frame.posstart > cache->frame.posstart) {
cache->next = pc->next;
pc->next = cache;
break;
}
}
}
stopDecodeGif(img);
return GDISP_IMAGE_ERR_OK;
nomemcleanup:
stopDecodeGif(img);
gdispImageFree(img, cache, sizeof(gifimgcache) + priv->frame.palsize*sizeof(color_t) + priv->frame.width*priv->frame.height);
return GDISP_IMAGE_ERR_NOMEMORY;
baddatacleanup:
stopDecodeGif(img);
gdispImageFree(img, cache, sizeof(gifimgcache) + priv->frame.palsize*sizeof(color_t) + priv->frame.width*priv->frame.height);
return GDISP_IMAGE_ERR_BADDATA;
}
gdispImageError gdispGImageDraw_GIF(GDisplay *g, gdispImage *img, coord_t x, coord_t y, coord_t cx, coord_t cy, coord_t sx, coord_t sy) {
gdispImagePrivate_GIF * priv;
gifimgdecode * decode;
uint8_t * q = 0;
coord_t mx, my, fx, fy;
uint16_t cnt, gcnt;
uint8_t col;
priv = (gdispImagePrivate_GIF *)img->priv;
/* Handle previous frame disposing */
if (priv->dispose.flags & (GIFL_DISPOSECLEAR|GIFL_DISPOSEREST)) {
// Clip to the disposal area - clip area = mx,my -> fx, fy (sx,sy,cx,cy are unchanged)
mx = priv->dispose.x;
my = priv->dispose.y;
fx = priv->dispose.x+priv->dispose.width;
fy = priv->dispose.y+priv->dispose.height;
if (sx > mx) mx = sx;
if (sy > my) my = sy;
if (sx+cx <= fx) fx = sx+cx;
if (sy+cy <= fy) fy = sy+cy;
if (fx > mx && fy > my) {
// We only support clearing (not restoring). The specification says that we are allowed to do this.
// Calculate the bgcolor
// The spec says to restore the backgound color (priv->bgcolor) but in practice if there is transparency
// image decoders tend to assume that a restore to the transparent color is required instead
if (((priv->dispose.flags & GIFL_TRANSPARENT) /*&& priv->dispose.paltrans == priv->bgcolor*/) || priv->bgcolor >= priv->palsize)
gdispGFillArea(g, x+mx-sx, y+my-sy, fx-mx, fy-my, img->bgcolor);
else
gdispGFillArea(g, x+mx-sx, y+my-sy, fx-mx, fy-my, priv->palette[priv->bgcolor]);
}
}
/* Clip to just this frame - clip area = sx,sy -> fx, fy */
fx = priv->frame.x+priv->frame.width;
fy = priv->frame.y+priv->frame.height;
if (sx >= fx || sy >= fy || sx+cx < priv->frame.x || sy+cy < priv->frame.y) return GDISP_IMAGE_ERR_OK;
if (sx < priv->frame.x) { mx = priv->frame.x - sx; x += mx; cx -= mx; sx = priv->frame.x; }
if (sy < priv->frame.y) { my = priv->frame.y - sy; y += my; cy -= my; sy = priv->frame.y; }
if (sx+cx > fx) cx = fx-sx;
if (sy+cy > fy) cy = fy-sy;
// Make sx, sy relative to this frame so we are not adding priv->frame.x & priv->frame.y each time
sx -= priv->frame.x; sy -= priv->frame.y;
fx = sx + cx;
fy = sy + cy;
/* Draw from the image cache - if it exists */
if (priv->curcache) {
gifimgcache * cache;
cache = priv->curcache;
q = cache->imagebits+priv->frame.width*sy+sx;
for(my=sy; my < fy; my++, q += priv->frame.width - cx) {
for(gcnt=0, mx=sx, cnt=0; mx < fx; mx++) {
col = *q++;
if ((priv->frame.flags & GIFL_TRANSPARENT) && col == priv->frame.paltrans) {
// We have a transparent pixel - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
continue;
}
priv->buf[gcnt++] = cache->palette[col];
if (gcnt >= GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE) {
// We have run out of buffer - dump it to the display
gdispGBlitArea(g, x+mx-sx-gcnt+1, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf);
gcnt = 0;
}
}
// We have finished the line - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); break;
}
}
return GDISP_IMAGE_ERR_OK;
}
/* Start the decode */
switch(startDecodeGif(img)) {
case GDISP_IMAGE_ERR_OK: break;
case GDISP_IMAGE_ERR_NOMEMORY: return GDISP_IMAGE_ERR_NOMEMORY;
case GDISP_IMAGE_ERR_BADDATA:
default: return GDISP_IMAGE_ERR_BADDATA;
}
decode = priv->decode;
// Check for interlacing
cnt = 0;
if (priv->frame.flags & GIFL_INTERLACE) {
// Every 8th row starting at row 0
for(my=0; my < priv->frame.height; my+=8) {
for(gcnt=0, mx=0; mx < priv->frame.width; mx++, q++, cnt--) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
mx++;
break;
}
q = decode->buf;
}
if (my >= sy && my < fy && mx >= sx && mx < fx) {
col = *q;
if ((priv->frame.flags & GIFL_TRANSPARENT) && col == priv->frame.paltrans) {
// We have a transparent pixel - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
continue;
}
priv->buf[gcnt++] = decode->palette[col];
if (gcnt >= GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE) {
// We have run out of buffer - dump it to the display
gdispGBlitArea(g, x+mx-sx-gcnt+1, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf);
gcnt = 0;
}
continue;
}
// We have finished the visible area - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
}
// We have finished the line - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); break;
}
}
// Every 8th row starting at row 4
for(my=4; my < priv->frame.height; my+=8) {
for(gcnt=0, mx=0; mx < priv->frame.width; mx++, q++, cnt--) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
mx++;
break;
}
q = decode->buf;
}
if (my >= sy && my < fy && mx >= sx && mx < fx) {
col = *q;
if ((priv->frame.flags & GIFL_TRANSPARENT) && col == priv->frame.paltrans) {
// We have a transparent pixel - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
continue;
}
priv->buf[gcnt++] = decode->palette[col];
if (gcnt >= GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE) {
// We have run out of buffer - dump it to the display
gdispGBlitArea(g, x+mx-sx-gcnt+1, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf);
gcnt = 0;
}
continue;
}
// We have finished the visible area - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
}
// We have finished the line - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); break;
}
}
// Every 4th row starting at row 2
for(my=2; my < priv->frame.height; my+=4) {
for(gcnt=0, mx=0; mx < priv->frame.width; mx++, q++, cnt--) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
mx++;
break;
}
q = decode->buf;
}
if (my >= sy && my < fy && mx >= sx && mx < fx) {
col = *q;
if ((priv->frame.flags & GIFL_TRANSPARENT) && col == priv->frame.paltrans) {
// We have a transparent pixel - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
continue;
}
priv->buf[gcnt++] = decode->palette[col];
if (gcnt >= GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE) {
// We have run out of buffer - dump it to the display
gdispGBlitArea(g, x+mx-sx-gcnt+1, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf);
gcnt = 0;
}
continue;
}
// We have finished the visible area - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
}
// We have finished the line - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); break;
}
}
// Every 2nd row starting at row 1
for(my=1; my < priv->frame.height; my+=2) {
for(gcnt=0, mx=0; mx < priv->frame.width; mx++, q++, cnt--) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
mx++;
break;
}
q = decode->buf;
}
if (my >= sy && my < fy && mx >= sx && mx < fx) {
col = *q;
if ((priv->frame.flags & GIFL_TRANSPARENT) && col == priv->frame.paltrans) {
// We have a transparent pixel - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
continue;
}
priv->buf[gcnt++] = decode->palette[col];
if (gcnt >= GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE) {
// We have run out of buffer - dump it to the display
gdispGBlitArea(g, x+mx-sx-gcnt+1, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf);
gcnt = 0;
}
continue;
}
// We have finished the visible area - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
}
// We have finished the line - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); break;
}
}
} else {
// Every row in sequence
for(my=0; my < priv->frame.height; my++) {
for(gcnt=0, mx=0; mx < priv->frame.width; mx++, q++, cnt--) {
if (!cnt) {
if (!(cnt = getBytesGif(img))) {
// Sometimes the image EOF is a bit early - treat the rest as transparent
if (decode->code_last != decode->code_eof)
goto baddatacleanup;
mx++;
break;
}
q = decode->buf;
}
if (my >= sy && my < fy && mx >= sx && mx < fx) {
col = *q;
if ((priv->frame.flags & GIFL_TRANSPARENT) && col == priv->frame.paltrans) {
// We have a transparent pixel - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
continue;
}
priv->buf[gcnt++] = decode->palette[col];
if (gcnt >= GDISP_IMAGE_GIF_BLIT_BUFFER_SIZE) {
// We have run out of buffer - dump it to the display
gdispGBlitArea(g, x+mx-sx-gcnt+1, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf);
gcnt = 0;
}
continue;
}
// We have finished the visible area - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); gcnt = 0; break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); gcnt = 0; break;
}
}
// We have finished the line - dump the buffer to the display
switch(gcnt) {
case 0: break;
case 1: gdispGDrawPixel(g, x+mx-sx-gcnt, y+my-sy, priv->buf[0]); break;
default: gdispGBlitArea(g, x+mx-sx-gcnt, y+my-sy, gcnt, 1, 0, 0, gcnt, priv->buf); break;
}
}
}
// We could be pedantic here but extra bytes won't hurt us
while (getBytesGif(img));
priv->frame.posend = gfileGetPos(img->f);
stopDecodeGif(img);
return GDISP_IMAGE_ERR_OK;
baddatacleanup:
stopDecodeGif(img);
return GDISP_IMAGE_ERR_BADDATA;
}
delaytime_t gdispImageNext_GIF(gdispImage *img) {
gdispImagePrivate_GIF * priv;
delaytime_t delay;
uint8_t blocksz;
priv = (gdispImagePrivate_GIF *)img->priv;
// Save the delay and convert to millisecs
delay = (delaytime_t)priv->frame.delay * 10;
// We need to get to the end of this frame
if (!priv->frame.posend) {
// We don't know where the end of the frame is yet - find it!
gfileSetPos(img->f, priv->frame.posimg+1); // Skip the code size byte too
while(1) {
if (gfileRead(img->f, &blocksz, 1) != 1)
return TIME_INFINITE;
if (!blocksz)
break;
gfileSetPos(img->f, gfileGetPos(img->f) + blocksz);
}
priv->frame.posend = gfileGetPos(img->f);
}
// Seek to the end of this frame
gfileSetPos(img->f, priv->frame.posend);
// Read the next frame descriptor
for(blocksz=0; blocksz < 2; blocksz++) { // 2 loops max to prevent cycling forever with a bad file
switch(initFrameGif(img)) {
case GDISP_IMAGE_ERR_OK: // Everything OK
return delay;
case GDISP_IMAGE_GIF_LOOP: // Back to the beginning
break;
case GDISP_IMAGE_GIF_EOF: // The real End-Of-File
case GDISP_IMAGE_ERR_BADDATA: // Oops - something wrong with the data
case GDISP_IMAGE_ERR_NOMEMORY: // Out of Memory
case GDISP_IMAGE_ERR_UNSUPPORTED: // Unsupported
default:
return TIME_INFINITE;
}
}
return TIME_INFINITE;
}
#endif /* GFX_USE_GDISP && GDISP_NEED_IMAGE && GDISP_NEED_IMAGE_GIF */
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