/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ #if !defined(LODEPNG) #ifndef __GNUC__ #pragma optimize("g", off) #endif #define TEST 0 #include "picopng.h" #ifndef DEBUG_ALL #define DEBUG_PNG 0 #else #define DEBUG_PNG DEBUG_ALL #endif #if DEBUG_PNG == 0 #define DBG(...) #else #define DBG(...) DebugLog(DEBUG_PNG, __VA_ARGS__) #endif CONST UINT32 pattern[28] = {0, 4, 0, 2, 0, 1, 0, 0, 0, 4, 0, 2, 0, 1, 8, 8, 4, 4, 2, 2, 1, 8, 8, 8, 4, 4, 2, 2 }; // values for the adam7 passes /*************************************************************************************************/ typedef struct png_alloc_node { struct png_alloc_node *prev, *next; void *addr; UINT32 size; } png_alloc_node_t; png_alloc_node_t *png_alloc_head = NULL; png_alloc_node_t *png_alloc_tail = NULL; png_alloc_node_t *png_alloc_find_node(void *addr, UINT32 size) { png_alloc_node_t *node; for (node = png_alloc_head; node; node = node->next) if (node->addr == addr){ if (size && (node->size != size)) { // Print(L"Error: Same address %p, size: %x, requested size: %x\n", node->addr, node->size, size); } break; } return node; } void png_alloc_add_node(void *addr, UINT32 size) { png_alloc_node_t *node; if (png_alloc_find_node(addr, size)) return; node = (__typeof__(node))AllocateZeroPool(sizeof (png_alloc_node_t)); node->addr = addr; node->size = size; node->prev = png_alloc_tail; node->next = NULL; png_alloc_tail = node; if (node->prev) node->prev->next = node; if (!png_alloc_head) png_alloc_head = node; } void png_alloc_remove_node(png_alloc_node_t *node) { if (node->prev) node->prev->next = node->next; if (node->next) node->next->prev = node->prev; if (node == png_alloc_head) png_alloc_head = node->next; if (node == png_alloc_tail) png_alloc_tail = node->prev; node->prev = node->next = node->addr = NULL; FreePool(node); } void *png_alloc_malloc(UINT32 size) { void *addr = (__typeof__(addr))AllocateZeroPool(size); png_alloc_add_node(addr, size); return addr; } void *png_alloc_realloc(void *addr, UINT32 oldSize, UINT32 newSize) { if (!addr) { return png_alloc_malloc(newSize); } if ( newSize > oldSize ) { png_alloc_node_t *old_node = png_alloc_find_node(addr, oldSize); if (old_node) { void *new_addr = (__typeof__(new_addr))ReallocatePool(oldSize, newSize, addr); old_node->addr = new_addr; old_node->size = newSize; return new_addr; } else { png_alloc_node_t* node = png_alloc_malloc(newSize); CopyMem(node->addr, addr, oldSize); // here, newSize is > oldSize return node->addr; } } else { return addr; } } void png_alloc_free(void *addr) { png_alloc_node_t *node = png_alloc_find_node(addr, 0); if (!node) return; png_alloc_remove_node(node); FreePool(addr); } void png_alloc_free_all() { while (png_alloc_tail) { void *addr = png_alloc_tail->addr; png_alloc_remove_node(png_alloc_tail); FreePool(addr); } } /*************************************************************************************************/ void vector32_cleanup(VECTOR_32 *p) { p->size = p->allocsize = 0; if (p->data) png_alloc_free(p->data); p->data = NULL; } UINT32 vector32_resize(VECTOR_32 *p, UINT32 size) { // returns 1 if success, 0 if failure ==> nothing done void *data; if (size * sizeof (UINT32) > p->allocsize) { UINT32 newsize = size * sizeof (UINT32) * 2; data = png_alloc_realloc(p->data, p->allocsize, newsize); if (data) { p->allocsize = newsize; p->data = (UINT32 *) data; p->size = size; } else return 0; } else p->size = size; return 1; } UINT32 vector32_resizev(VECTOR_32 *p, UINT32 size, UINT32 value) { // resize and give all new elements the value UINT32 oldsize = p->size, i; if (!vector32_resize(p, size)) return 0; for (i = oldsize; i < size; i++) p->data[i] = value; return 1; } void vector32_init(VECTOR_32 *p) { p->data = NULL; p->size = p->allocsize = 0; } VECTOR_32 *vector32_new(UINT32 size, UINT32 value) { VECTOR_32 *p = png_alloc_malloc(sizeof (VECTOR_32)); vector32_init(p); if (size && !vector32_resizev(p, size, value)) return NULL; return p; } /*************************************************************************************************/ void vector8_cleanup(VECTOR_8 *p) { p->size = p->allocsize = 0; if (p->data) png_alloc_free(p->data); p->data = NULL; } UINT32 vector8_resize(VECTOR_8 *p, UINT32 size) { // returns 1 if success, 0 if failure ==> nothing done // xxx: the use of sizeof UINT32 here seems like a bug (this descends from the lodepng vector // compatibility functions which do the same). without this there is corruption in certain cases, // so this was probably done to cover up allocation bug(s) in the original picopng code! void *data; if (size * sizeof (UINT32) > p->allocsize) { UINT32 newsize = size * sizeof (UINT32) * 2; data = png_alloc_realloc(p->data, p->allocsize, newsize); if (data) { p->allocsize = newsize; p->data = (UINT8 *) data; p->size = size; } else return 0; // error: not enough memory } else p->size = size; return 1; } UINT32 vector8_resizev(VECTOR_8 *p, UINT32 size, UINT8 value) { // resize and give all new elements the value UINT32 oldsize = p->size, i; if (!vector8_resize(p, size)) return 0; for (i = oldsize; i < size; i++) p->data[i] = value; return 1; } void vector8_init(VECTOR_8 *p) { p->data = NULL; p->size = p->allocsize = 0; } VECTOR_8 *vector8_new(UINT32 size, UINT8 value) { VECTOR_8 *p = png_alloc_malloc(sizeof (VECTOR_8)); vector8_init(p); if (size && !vector8_resizev(p, size, value)) return NULL; return p; } VECTOR_8 *vector8_copy(VECTOR_8 *p) { VECTOR_8 *q = vector8_new(p->size, 0); UINT32 n; for (n = 0; n < q->size; n++) q->data[n] = p->data[n]; return q; } /*************************************************************************************************/ const UINT32 LENBASE[29] = { 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258 }; const UINT32 LENEXTRA[29] = { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0 }; const UINT32 DISTBASE[30] = { 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577 }; const UINT32 DISTEXTRA[30] = { 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13 }; // code length code lengths const UINT32 CLCL[19] = { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 }; /*************************************************************************************************/ typedef struct { // 2D representation of a huffman tree: The one dimension is "0" or "1", the other contains all // nodes and leaves of the tree. VECTOR_32 *tree2d; } HuffmanTree; HuffmanTree *HuffmanTree_new() { HuffmanTree *tree = png_alloc_malloc(sizeof (HuffmanTree)); tree->tree2d = NULL; return tree; } int HuffmanTree_makeFromLengths(HuffmanTree *tree, const VECTOR_32 *bitlen, UINT32 maxbitlen) { // make tree given the lengths VECTOR_32 *tree2d; UINT32 bits, n, i; UINT32 numcodes = (UINT32) bitlen->size, treepos = 0, nodefilled = 0; VECTOR_32 *tree1d, *blcount, *nextcode; tree1d = vector32_new(numcodes, 0); blcount = vector32_new(maxbitlen + 1, 0); nextcode = vector32_new(maxbitlen + 1, 0); for (bits = 0; bits < numcodes; bits++) blcount->data[bitlen->data[bits]]++; // count number of instances of each code length for (bits = 1; bits <= maxbitlen; bits++) nextcode->data[bits] = (nextcode->data[bits - 1] + blcount->data[bits - 1]) << 1; for (n = 0; n < numcodes; n++) if (bitlen->data[n] != 0) tree1d->data[n] = nextcode->data[bitlen->data[n]]++; // generate all the codes // 0x7fff here means the tree2d isn't filled there yet tree2d = vector32_new(numcodes * 2, 0x7fff); tree->tree2d = tree2d; for (n = 0; n < numcodes; n++) // the codes for (i = 0; i < bitlen->data[n]; i++) { // the bits for this code UINT32 bit = (tree1d->data[n] >> (bitlen->data[n] - i - 1)) & 1; if (treepos > numcodes - 2) return 55; if (tree2d->data[2 * treepos + bit] == 0x7fff) { if (i + 1 == bitlen->data[n]) { tree2d->data[2 * treepos + bit] = n; treepos = 0; } else { tree2d->data[2 * treepos + bit] = ++nodefilled + numcodes; treepos = nodefilled; } } else treepos = tree2d->data[2 * treepos + bit] - numcodes; } return 0; } int HuffmanTree_decode(const HuffmanTree *tree, BOOLEAN *decoded, UINT32 *result, UINT32 *treepos, UINT32 bit) { // Decodes a symbol from the tree const VECTOR_32 *tree2d = tree->tree2d; UINT32 numcodes = (UINT32) tree2d->size / 2; if (*treepos >= numcodes) return 11; *result = tree2d->data[2 * (*treepos) + bit]; *decoded = (*result < numcodes); *treepos = *decoded ? 0 : *result - numcodes; return 0; } /*************************************************************************************************/ int Inflator_error; UINT32 Zlib_readBitFromStream(UINT32 *bitp, const UINT8 *bits) { UINT32 result = (bits[*bitp >> 3] >> (*bitp & 0x7)) & 1; (*bitp)++; return result; } UINT32 Zlib_readBitsFromStream(UINT32 *bitp, const UINT8 *bits, UINT32 nbits) { UINT32 i, result = 0; for (i = 0; i < nbits; i++) result += (Zlib_readBitFromStream(bitp, bits)) << i; return result; } void Inflator_generateFixedTrees(HuffmanTree *tree, HuffmanTree *treeD) { // get the tree of a deflated block with fixed tree UINT32 i; VECTOR_32 *bitlen, *bitlenD; bitlen = vector32_new(288, 8); bitlenD = vector32_new(32, 5); for (i = 144; i <= 255; i++) bitlen->data[i] = 9; for (i = 256; i <= 279; i++) bitlen->data[i] = 7; HuffmanTree_makeFromLengths(tree, bitlen, 15); HuffmanTree_makeFromLengths(treeD, bitlenD, 15); } UINT32 Inflator_huffmanDecodeSymbol(const UINT8 *in, UINT32 *bp, const HuffmanTree *codetree, UINT32 inlength) { // decode a single symbol from given list of bits with given code tree. returns the symbol BOOLEAN decoded = FALSE; UINT32 ct = 0; UINT32 treepos = 0; for (;;) { if ((*bp & 0x07) == 0 && (*bp >> 3) > inlength) { Inflator_error = 10; // error: end reached without endcode return 0; } Inflator_error = HuffmanTree_decode(codetree, &decoded, &ct, &treepos, Zlib_readBitFromStream(bp, in)); if (Inflator_error) return 0; // stop, an error happened if (decoded) return ct; } } void Inflator_getTreeInflateDynamic(HuffmanTree *tree, HuffmanTree *treeD, const UINT8 *in, UINT32 *bp, UINT32 inlength) { // get the tree of a deflated block with dynamic tree, the tree itself is also Huffman // compressed with a known tree UINT32 i, n; UINT32 HLIT; UINT32 HDIST; UINT32 HCLEN; UINT32 replength; VECTOR_32 *codelengthcode; HuffmanTree *codelengthcodetree = HuffmanTree_new(); // the code tree for code length codes VECTOR_32 *bitlen, *bitlenD; bitlen = vector32_new(288, 0); bitlenD = vector32_new(32, 0); if (*bp >> 3 >= inlength - 2) { Inflator_error = 49; // the bit pointer is or will go past the memory png_alloc_free(codelengthcodetree); return; } HLIT = Zlib_readBitsFromStream(bp, in, 5) + 257; // number of literal/length codes + 257 HDIST = Zlib_readBitsFromStream(bp, in, 5) + 1; // number of dist codes + 1 HCLEN = Zlib_readBitsFromStream(bp, in, 4) + 4; // number of code length codes + 4 // lengths of tree to decode the lengths of the dynamic tree codelengthcode = vector32_new(19, 0); for (i = 0; i < 19; i++) codelengthcode->data[CLCL[i]] = (i < HCLEN) ? Zlib_readBitsFromStream(bp, in, 3) : 0; Inflator_error = HuffmanTree_makeFromLengths(codelengthcodetree, codelengthcode, 7); if (Inflator_error) return; for (i = 0; i < HLIT + HDIST; ) { UINT32 code = Inflator_huffmanDecodeSymbol(in, bp, codelengthcodetree, inlength); if (Inflator_error) return; if (code <= 15) { // a length code if (i < HLIT) bitlen->data[i++] = code; else bitlenD->data[i++ - HLIT] = code; } else if (code == 16) { // repeat previous UINT32 value; // set value to the previous code if (*bp >> 3 >= inlength) { Inflator_error = 50; // error, bit pointer jumps past memory return; } replength = 3 + Zlib_readBitsFromStream(bp, in, 2); if ((i - 1) < HLIT) value = bitlen->data[i - 1]; else value = bitlenD->data[i - HLIT - 1]; for (n = 0; n < replength; n++) { // repeat this value in the next lengths if (i >= HLIT + HDIST) { Inflator_error = 13; // error: i is larger than the amount of codes return; } if (i < HLIT) bitlen->data[i++] = value; else bitlenD->data[i++ - HLIT] = value; } } else if (code == 17) { if (*bp >> 3 >= inlength) { Inflator_error = 50; // error, bit pointer jumps past memory return; } replength = 3 + Zlib_readBitsFromStream(bp, in, 3); for (n = 0; n < replength; n++) { // repeat this value in the next lengths if (i >= HLIT + HDIST) { Inflator_error = 14; // error: i is larger than the amount of codes return; } if (i < HLIT) bitlen->data[i++] = 0; else bitlenD->data[i++ - HLIT] = 0; } } else if (code == 18) { if (*bp >> 3 >= inlength) { Inflator_error = 50; return; } replength = 11 + Zlib_readBitsFromStream(bp, in, 7); for (n = 0; n < replength; n++) { if (i >= HLIT + HDIST) { Inflator_error = 15; // error: i is larger than the amount of codes return; } if (i < HLIT) bitlen->data[i++] = 0; else bitlenD->data[i++ - HLIT] = 0; } } else { Inflator_error = 16; // error: an nonexitent code appeared. This can never happen. return; } } if (bitlen->data[256] == 0) { Inflator_error = 64; // the length of the end code 256 must be larger than 0 return; } // now we've finally got HLIT and HDIST, so generate the code trees, and the function is done Inflator_error = HuffmanTree_makeFromLengths(tree, bitlen, 15); if (Inflator_error) return; Inflator_error = HuffmanTree_makeFromLengths(treeD, bitlenD, 15); if (Inflator_error) return; } void Inflator_inflateHuffmanBlock(VECTOR_8 *out, const UINT8 *in, UINT32 *bp, UINT32 *pos, UINT32 inlength, UINT32 btype) { HuffmanTree *codetree, *codetreeD; // the code tree for Huffman codes, dist codes codetree = HuffmanTree_new(); codetreeD = HuffmanTree_new(); if (btype == 1) Inflator_generateFixedTrees(codetree, codetreeD); else if (btype == 2) { Inflator_getTreeInflateDynamic(codetree, codetreeD, in, bp, inlength); if (Inflator_error) return; } for (;;) { UINT32 code = Inflator_huffmanDecodeSymbol(in, bp, codetree, inlength); if (Inflator_error) return; if (code == 256) // end code return; else if (code <= 255) { // literal symbol if (*pos >= out->size) vector8_resize(out, (*pos + 1) * 2); // reserve more room out->data[(*pos)++] = (UINT8) code; } else if (code >= 257 && code <= 285) { // length code UINT32 length = LENBASE[code - 257], numextrabits = LENEXTRA[code - 257]; UINT32 codeD; UINT32 dist,numextrabitsD; UINT32 start,back; UINT32 i; if ((*bp >> 3) >= inlength) { Inflator_error = 51; // error, bit pointer will jump past memory return; } length += Zlib_readBitsFromStream(bp, in, numextrabits); codeD = Inflator_huffmanDecodeSymbol(in, bp, codetreeD, inlength); if (Inflator_error) return; if (codeD > 29) { Inflator_error = 18; // error: invalid dist code (30-31 are never used) return; } dist = DISTBASE[codeD] ; numextrabitsD = DISTEXTRA[codeD]; if ((*bp >> 3) >= inlength) { Inflator_error = 51; // error, bit pointer will jump past memory return; } dist += Zlib_readBitsFromStream(bp, in, numextrabitsD); start = *pos; back = start - dist; // backwards if (*pos + length >= out->size) vector8_resize(out, (*pos + length) * 2); // reserve more room for (i = 0; i < length; i++) { out->data[(*pos)++] = out->data[back++]; if (back >= start) back = start - dist; } } } } void Inflator_inflateNoCompression(VECTOR_8 *out, const UINT8 *in, UINT32 *bp, UINT32 *pos, UINT32 inlength) { UINT32 LEN,NLEN; UINT32 p; UINT32 n; while ((*bp & 0x7) != 0) (*bp)++; // go to first boundary of byte p = *bp / 8; if (p >= inlength - 4) { Inflator_error = 52; // error, bit pointer will jump past memory return; } LEN = in[p] + 256 * in[p + 1]; NLEN = in[p + 2] + 256 * in[p + 3]; p += 4; if (LEN + NLEN != 65535) { Inflator_error = 21; // error: NLEN is not one's complement of LEN return; } if (*pos + LEN >= out->size) vector8_resize(out, *pos + LEN); if (p + LEN > inlength) { Inflator_error = 23; // error: reading outside of in buffer return; } for (n = 0; n < LEN; n++) out->data[(*pos)++] = in[p++]; // read LEN bytes of literal data *bp = p * 8; } void Inflator_inflate(VECTOR_8 *out, const VECTOR_8 *in, UINT32 inpos) { UINT32 bp = 0, pos = 0; // bit pointer and byte pointer UINT32 BFINAL = 0; UINT32 BTYPE; Inflator_error = 0; while (!BFINAL && !Inflator_error) { if (bp >> 3 >= in->size) { Inflator_error = 52; // error, bit pointer will jump past memory return; } BFINAL = Zlib_readBitFromStream(&bp, &in->data[inpos]); BTYPE = Zlib_readBitFromStream(&bp, &in->data[inpos]); BTYPE += 2 * Zlib_readBitFromStream(&bp, &in->data[inpos]); if (BTYPE == 3) { Inflator_error = 20; // error: invalid BTYPE return; } else if (BTYPE == 0) Inflator_inflateNoCompression(out, &in->data[inpos], &bp, &pos, in->size); else Inflator_inflateHuffmanBlock(out, &in->data[inpos], &bp, &pos, in->size, BTYPE); } if (!Inflator_error) vector8_resize(out, pos); // Only now we know the TRUE size of out, resize it to that } /*************************************************************************************************/ INT32 Zlib_decompress(VECTOR_8 *out, const VECTOR_8 *in) // returns error value { UINT32 CM,CINFO,FDICT; if (in->size < 2) { return 53; // error, size of zlib data too small } if ((in->data[0] * 256 + in->data[1]) % 31 != 0) { // error: 256 * in->data[0] + in->data[1] must be a multiple of 31, the FCHECK value is // supposed to be made that way return 24; } CM = in->data[0] & 15; CINFO = (in->data[0] >> 4) & 15; FDICT = (in->data[1] >> 5) & 1; // DBG("compression method %d and CINFO=%d FDICT=%d\n", CM, CINFO, FDICT); if (CM != 8 || CINFO > 7){ // DBG("Error 25 : compression method %d and CINFO=%d FDICT=%d\n", CM, CINFO, FDICT); // error: only compression method 8: inflate with sliding window of 32k is supported by // the PNG spec return 25; } if (FDICT != 0){ // DBG("Error 26 : compression method %d and CINFO=%d FDICT=%d\n", CM, CINFO, FDICT); // error: the specification of PNG says about the zlib stream: "The additional flags shall // not specify a preset dictionary." return 26; } Inflator_inflate(out, in, 2); return Inflator_error; // note: adler32 checksum was skipped and ignored } /*************************************************************************************************/ #define PNG_SIGNATURE 0x0a1a0a0d474e5089ull #define CHUNK_IHDR 0x52444849 #define CHUNK_IDAT 0x54414449 #define CHUNK_IEND 0x444e4549 #define CHUNK_PLTE 0x45544c50 #define CHUNK_tRNS 0x534e5274 INT32 PNG_error; UINT32 PNG_readBitFromReversedStream(UINT32 *bitp, const UINT8 *bits) { UINT32 result = (bits[*bitp >> 3] >> (7 - (*bitp & 0x7))) & 1; (*bitp)++; return result; } UINT32 PNG_readBitsFromReversedStream(UINT32 *bitp, const UINT8 *bits, UINT32 nbits) { UINT32 i, result = 0; for (i = nbits - 1; i < nbits; i--) result += ((PNG_readBitFromReversedStream(bitp, bits)) << i); return result; } void PNG_setBitOfReversedStream(UINT32 *bitp, UINT8 *bits, UINT32 bit) { bits[*bitp >> 3] |= (bit << (7 - (*bitp & 0x7))); (*bitp)++; } UINT32 PNG_read32bitInt(const UINT8 *buffer) { return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; } UINT32 PNG_read32bitLE(const UINT8 *buffer) { return (buffer[3] << 24) | (buffer[2] << 16) | (buffer[1] << 8) | buffer[0]; } INT32 PNG_checkColorValidity(UINT32 colorType, UINT32 bd) // return type is a LodePNG error code { if ((colorType == 2 || colorType == 4 || colorType == 6)) { if (!(bd == 8 || bd == 16)) return 37; else return 0; } else if (colorType == 0) { if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) return 37; else return 0; } else if (colorType == 3) { if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8)) return 37; else return 0; } else return 31; // nonexistent color type } UINT32 PNG_getBpp(const PNG_INFO *info) { UINT32 bitDepth, colorType; bitDepth = info->bitDepth; colorType = info->colorType; if (colorType == 2) return (3 * bitDepth); else if (colorType >= 4) return (colorType - 2) * bitDepth; else return bitDepth; } void PNG_readPngHeader(PNG_INFO *info, const UINT8 *in, UINT32 inlength) { // read the information from the header and store it in the Info if (inlength < 29) { PNG_error = 27; // error: the data length is smaller than the length of the header return; } if (*(UINT64 *) in != PNG_SIGNATURE) { PNG_error = 28; // no PNG signature return; } if (*(UINT32 *) &in[12] != CHUNK_IHDR) { PNG_error = 29; // error: it doesn't start with a IHDR chunk! return; } info->width = PNG_read32bitInt(&in[16]); info->height = PNG_read32bitInt(&in[20]); info->bitDepth = in[24]; info->colorType = in[25]; info->compressionMethod = in[26]; if (in[26] != 0) { PNG_error = 32; // error: only compression method 0 is allowed in the specification DBG("error: only compression method 0 is allowed in the specification\n"); return; } info->filterMethod = in[27]; if (in[27] != 0) { PNG_error = 33; // error: only filter method 0 is allowed in the specification DBG("error: only filter method 0 is allowed in the specification\n"); return; } info->interlaceMethod = in[28]; if (in[28] > 1) { PNG_error = 34; // error: only interlace methods 0 and 1 exist in the specification DBG("error: only interlace method 0 and 1 exist in the specification\n"); return; } PNG_error = PNG_checkColorValidity(info->colorType, info->bitDepth); if (PNG_error) { DBG("error: checkColorValidity =%d\n", PNG_error); } } INT32 PNG_paethPredictor(INT32 a, INT32 b, INT32 c) // Paeth predicter, used by PNG filter type 4 { INT32 p, pa, pb, pc; p = a + b - c; pa = p > a ? (p - a) : (a - p); pb = p > b ? (p - b) : (b - p); pc = p > c ? (p - c) : (c - p); return (pa <= pb && pa <= pc) ? a : (pb <= pc ? b : c); } void PNG_unFilterScanline(UINT8 *recon, const UINT8 *scanline, const UINT8 *precon, UINT32 bytewidth, UINT32 filterType, UINT32 length) { UINT32 i; switch (filterType) { case 0: for (i = 0; i < length; i++) recon[i] = scanline[i]; break; case 1: for (i = 0; i < bytewidth; i++) recon[i] = scanline[i]; for (i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth]; break; case 2: if (precon) for (i = 0; i < length; i++) recon[i] = scanline[i] + precon[i]; else for (i = 0; i < length; i++) recon[i] = scanline[i]; break; case 3: if (precon) { for (i = 0; i < bytewidth; i++) recon[i] = scanline[i] + precon[i] / 2; for (i = bytewidth; i < length; i++) recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); } else { for (i = 0; i < bytewidth; i++) recon[i] = scanline[i]; for (i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth] / 2; } break; case 4: if (precon) { for (i = 0; i < bytewidth; i++) recon[i] = (UINT8) (scanline[i] + PNG_paethPredictor(0, precon[i], 0)); for (i = bytewidth; i < length; i++) recon[i] = (UINT8) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], precon[i], precon[i - bytewidth])); } else { for (i = 0; i < bytewidth; i++) recon[i] = scanline[i]; for (i = bytewidth; i < length; i++) recon[i] = (UINT8) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], 0, 0)); } break; default: PNG_error = 36; // error: nonexistent filter type given DBG("error: nonexistent filter type given\n"); return; } } void PNG_adam7Pass(UINT8 *out, UINT8 *linen, UINT8 *lineo, const UINT8 *in, UINT32 w, UINT32 passleft, UINT32 passtop, UINT32 spacex, UINT32 spacey, UINT32 passw, UINT32 passh, UINT32 bpp) { // filter and reposition the pixels into the output when the image is Adam7 interlaced. This // function can only do it after the full image is already decoded. The out buffer must have // the correct allocated memory size already. UINT32 bytewidth,linelength,y; if (passw == 0) return; bytewidth = (bpp + 7) / 8; linelength = 1 + ((bpp * passw + 7) / 8); for (y = 0; y < passh; y++) { UINT32 i, b; UINT8 filterType = in[y * linelength], *prevline = (y == 0) ? 0 : lineo; UINT8 *temp; PNG_unFilterScanline(linen, &in[y * linelength + 1], prevline, bytewidth, filterType, (w * bpp + 7) / 8); if (PNG_error) return; if (bpp >= 8) for (i = 0; i < passw; i++) for (b = 0; b < bytewidth; b++) // b = current byte of this pixel out[bytewidth * w * (passtop + spacey * y) + bytewidth * (passleft + spacex * i) + b] = linen[bytewidth * i + b]; else for (i = 0; i < passw; i++) { UINT32 obp, bp; obp = bpp * w * (passtop + spacey * y) + bpp * (passleft + spacex * i); bp = i * bpp; for (b = 0; b < bpp; b++) PNG_setBitOfReversedStream(&obp, out, PNG_readBitFromReversedStream(&bp, linen)); } temp = linen; linen = lineo; lineo = temp; // swap the two buffer pointers "line old" and "line new" } } INT32 PNG_convert(const PNG_INFO *info, VECTOR_8 *out, const UINT8 *in) { // converts from any color type to 32-bit. return value = LodePNG error code UINT32 i, c, numpixels,bp; UINT32 bitDepth, colorType; UINT8 *out_data; bitDepth = info->bitDepth; colorType = info->colorType; numpixels = info->width * info->height; bp = 0; vector8_resize(out, numpixels * 4); out_data = out->size ? out->data : 0; if (bitDepth == 8 && colorType == 0) // greyscale for (i = 0; i < numpixels; i++) { out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[i]; out_data[4 * i + 3] = (info->key_defined && (in[i] == info->key_r)) ? 0 : 255; } else if (bitDepth == 8 && colorType == 2) // RGB color for (i = 0; i < numpixels; i++) { for (c = 0; c < 3; c++) out_data[4 * i + c] = in[3 * i + c]; out_data[4 * i + 3] = (info->key_defined && (in[3 * i + 0] == info->key_r) && (in[3 * i + 1] == info->key_g) && (in[3 * i + 2] == info->key_b)) ? 0 : 255; } else if (bitDepth == 8 && colorType == 3) // indexed color (palette) for (i = 0; i < numpixels; i++) { if (4U * in[i] >= info->palette->size) return 46; for (c = 0; c < 4; c++) // get rgb colors from the palette out_data[4 * i + c] = info->palette->data[4 * in[i] + c]; } else if (bitDepth == 8 && colorType == 4) // greyscale with alpha for (i = 0; i < numpixels; i++) { out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i + 0]; out_data[4 * i + 3] = in[2 * i + 1]; } else if (bitDepth == 8 && colorType == 6) for (i = 0; i < numpixels; i++) for (c = 0; c < 4; c++) out_data[4 * i + c] = in[4 * i + c]; // RGB with alpha else if (bitDepth == 16 && colorType == 0) // greyscale for (i = 0; i < numpixels; i++) { out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i]; out_data[4 * i + 3] = (info->key_defined && (256U * in[i] + in[i + 1] == info->key_r)) ? 0 : 255; } else if (bitDepth == 16 && colorType == 2) // RGB color for (i = 0; i < numpixels; i++) { for (c = 0; c < 3; c++) out_data[4 * i + c] = in[6 * i + 2 * c]; out_data[4 * i + 3] = (info->key_defined && (256U * in[6 * i + 0] + in[6 * i + 1] == info->key_r) && (256U * in[6 * i + 2] + in[6 * i + 3] == info->key_g) && (256U * in[6 * i + 4] + in[6 * i + 5] == info->key_b)) ? 0 : 255; } else if (bitDepth == 16 && colorType == 4) // greyscale with alpha for (i = 0; i < numpixels; i++) { out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[4 * i]; // msb out_data[4 * i + 3] = in[4 * i + 2]; } else if (bitDepth == 16 && colorType == 6) for (i = 0; i < numpixels; i++) for (c = 0; c < 4; c++) out_data[4 * i + c] = in[8 * i + 2 * c]; // RGB with alpha else if (bitDepth < 8 && colorType == 0) // greyscale for (i = 0; i < numpixels; i++) { UINT32 value = (PNG_readBitsFromReversedStream(&bp, in, bitDepth) * 255) / ((1 << bitDepth) - 1); // scale value from 0 to 255 out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = (UINT8) value; out_data[4 * i + 3] = (info->key_defined && value && (((1U << bitDepth) - 1U) == info->key_r) && ((1U << bitDepth) - 1U)) ? 0 : 255; } else if (bitDepth < 8 && colorType == 3) // palette for (i = 0; i < numpixels; i++) { UINT32 value = PNG_readBitsFromReversedStream(&bp, in, bitDepth); if (4 * value >= info->palette->size) return 47; for (c = 0; c < 4; c++) // get rgb colors from the palette out_data[4 * i + c] = info->palette->data[4 * value + c]; } return 0; } PNG_INFO *PNG_info_new() { PNG_INFO *info = png_alloc_malloc(sizeof (PNG_INFO)); UINT32 i; for (i = 0; i < sizeof (PNG_INFO); i++) ((UINT8 *) info)[i] = 0; info->palette = vector8_new(0, 0); info->image = vector8_new(0, 0); return info; } PNG_INFO *PNG_decode(/* const*/ UINT8 *in, UINT32 size) { UINT32 pos ; VECTOR_8 *idat; BOOLEAN IEND; //,known_type; UINT32 bpp; PNG_INFO *info; VECTOR_8 *scanlines; // now the out buffer will be filled UINT32 bytewidth, outlength ; UINT8 *out_data; PNG_error = 0; if (size == 0 || in == 0) { PNG_error = 48; // the given data is empty DBG("the given data is empty\n"); return NULL; } info = PNG_info_new(); PNG_readPngHeader(info, in, size); if (PNG_error){ DBG("readPngHeader PNG_error=%d\n", PNG_error); return NULL; } pos = 33; // first byte of the first chunk after the header idat = NULL; // the data from idat chunks IEND = FALSE; // known_type = TRUE; info->key_defined = FALSE; // loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. IDAT data is // put at the start of the in buffer while (!IEND) { UINT32 i, j; UINT32 chunkLength ; UINT32 chunkType; UINT32 offset = 0; if (pos + 8 >= size) { PNG_error = 30; // error: size of the in buffer too small to contain next chunk DBG("error: size of the in buffer too small to contain next chunk size=%d\n", size); return NULL; } chunkLength = PNG_read32bitInt(&in[pos]); //big endian? Yes! pos += 4; if (chunkLength > 0x7fffffff) { PNG_error = 63; return NULL; } if (pos + chunkLength >= size) { PNG_error = 35; // error: size of the in buffer too small to contain next chunk return NULL; } // chunkType = *(UINT32 *) &in[pos]; chunkType = PNG_read32bitLE(&in[pos]); //read as LE to compare with our constants switch (chunkType) { case CHUNK_IDAT: if (idat) { offset = idat->size; vector8_resize(idat, offset + chunkLength); } else idat = vector8_new(chunkLength, 0); for (i = 0; i < chunkLength; i++) idat->data[offset + i] = in[pos + 4 + i]; pos += (4 + chunkLength); break; case CHUNK_IEND: pos += 4; IEND = TRUE; break; case CHUNK_PLTE: // PLTE: palette chunk pos += 4; // go after the 4 letters vector8_resize(info->palette, 4 * (chunkLength / 3)); if (info->palette->size > (4 * 256)) { PNG_error = 38; // error: palette too big return NULL; } for (i = 0; i < info->palette->size; i += 4) { for (j = 0; j < 3; j++) info->palette->data[i + j] = in[pos++]; // RGB info->palette->data[i + 3] = 255; // alpha } break; case CHUNK_tRNS: // tRNS: palette transparency chunk pos += 4; // go after the 4 letters switch (info->colorType) { case 0: if (chunkLength != 2) { PNG_error = 40; // error: this chunk must be 2 bytes for greyscale image return NULL; } info->key_defined = TRUE; info->key_r = info->key_g = info->key_b = 256 * in[pos] + in[pos + 1]; pos += 2; break; case 2: if (chunkLength != 6) { PNG_error = 41; // error: this chunk must be 6 bytes for RGB image return NULL; } info->key_defined = TRUE; info->key_r = 256 * in[pos] + in[pos + 1]; pos += 2; info->key_g = 256 * in[pos] + in[pos + 1]; pos += 2; info->key_b = 256 * in[pos] + in[pos + 1]; pos += 2; break; case 3: if (4 * chunkLength > info->palette->size) { PNG_error = 39; // error: more alpha values given than there are palette entries return NULL; } for (i = 0; i < chunkLength; i++) info->palette->data[4 * i + 3] = in[pos++]; break; default: PNG_error = 42; // error: tRNS chunk not allowed for other color models return NULL; break; } break; default: // it's not an implemented chunk type, so ignore it: skip over the data if (!(in[pos + 0] & 0x20)) { // error: unknown critical chunk (5th bit of first byte of chunk type is 0) PNG_error = 69; return NULL; } pos += (chunkLength + 4); // skip 4 letters and uninterpreted data of unimplemented chunk // known_type = FALSE; break; } pos += 4; // step over CRC (which is ignored) } bpp = PNG_getBpp(info); // now the out buffer will be filled scanlines = vector8_new(((info->width * (info->height * bpp + 7)) / 8) + info->height, 0); PNG_error = Zlib_decompress(scanlines, idat); if (PNG_error) { // DBG("Zlib_decompress return %d", PNG_error); return NULL; // stop if the zlib decompressor returned an error } bytewidth = (bpp + 7) / 8; outlength = (info->height * info->width * bpp + 7) / 8; vector8_resize(info->image, outlength); // time to fill the out buffer out_data = outlength ? info->image->data : 0; if (info->interlaceMethod == 0) { // no interlace, just filter UINT32 y, obp, bp; UINT32 linestart, linelength; linestart = 0; // length in bytes of a scanline, excluding the filtertype byte linelength = (info->width * bpp + 7) / 8; if (bpp >= 8) // byte per byte for (y = 0; y < info->height; y++) { UINT32 filterType = scanlines->data[linestart]; const UINT8 *prevline; prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth]; PNG_unFilterScanline(&out_data[linestart - y], &scanlines->data[linestart + 1], prevline, bytewidth, filterType, linelength); if (PNG_error) { // DBG("PNG_unFilterScanline 1 return %d", PNG_error); return NULL; } linestart += (1 + linelength); // go to start of next scanline } else { // less than 8 bits per pixel, so fill it up bit per bit VECTOR_8 *templine; // only used if bpp < 8 templine = vector8_new((info->width * bpp + 7) >> 3, 0); for (y = 0, obp = 0; y < info->height; y++) { UINT32 filterType = scanlines->data[linestart]; const UINT8 *prevline; prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth]; PNG_unFilterScanline(templine->data, &scanlines->data[linestart + 1], prevline, bytewidth, filterType, linelength); if (PNG_error) { // DBG("PNG_unFilterScanline 2 return %d", PNG_error); return NULL; } for (bp = 0; bp < info->width * bpp;) PNG_setBitOfReversedStream(&obp, out_data, PNG_readBitFromReversedStream(&bp, templine->data)); linestart += (1 + linelength); // go to start of next scanline } } } else { // interlaceMethod is 1 (Adam7) INT32 i; VECTOR_8 *scanlineo, *scanlinen; // "old" and "new" scanline #ifndef __GNUC__ #pragma warning(disable: 4204) #endif UINT32 passw[7] = { (info->width + 7) / 8, (info->width + 3) / 8, (info->width + 3) / 4, (info->width + 1) / 4, (info->width + 1) / 2, (info->width + 0) / 2, (info->width + 0) / 1 }; UINT32 passh[7] = { (info->height + 7) / 8, (info->height + 7) / 8, (info->height + 3) / 8, (info->height + 3) / 4, (info->height + 1) / 4, (info->height + 1) / 2, (info->height + 0) / 2 }; UINT32 passstart[7]; //= { 0 }; for (i=0; i<7; i++) { passstart[i] = 0; } // UINT32 pattern[28] = { 0, 4, 0, 2, 0, 1, 0, 0, 0, 4, 0, 2, 0, 1, 8, 8, 4, 4, 2, 2, 1, 8, 8, // 8, 4, 4, 2, 2 }; // values for the adam7 passes for (i = 0; i < 6; i++) passstart[i + 1] = passstart[i] + passh[i] * ((passw[i] ? 1 : 0) + (passw[i] * bpp + 7) / 8); scanlineo = vector8_new((info->width * bpp + 7) / 8, 0); scanlinen = vector8_new((info->width * bpp + 7) / 8, 0); for (i = 0; i < 7; i++) PNG_adam7Pass(out_data, scanlinen->data, scanlineo->data, &scanlines->data[passstart[i]], info->width, pattern[i], pattern[i + 7], pattern[i + 14], pattern[i + 21], passw[i], passh[i], bpp); } if (info->colorType != 6 || info->bitDepth != 8) { // conversion needed VECTOR_8 *copy = vector8_copy(info->image); // xxx: is this copy necessary? PNG_error = PNG_convert(info, info->image, copy->data); if (PNG_error) { // DBG("PNG_convert return %d", PNG_error); return NULL; } } return info; } /**********************************************************************************************/ EG_IMAGE * egDecodePNG(IN UINT8 *FileData, IN UINTN FileDataLength, IN BOOLEAN WantAlpha) { EG_IMAGE *NewImage; PNG_INFO *info; // UINT8 AlphaValue; EG_PIXEL *Pixel; INTN x, y; // read and check header if (FileDataLength < sizeof(BMP_IMAGE_HEADER) || FileData == NULL) return NULL; // read and check header PNG_error = 0; info = PNG_decode(FileData, (UINT32)FileDataLength); if (info == NULL || PNG_error) { // DBG("PNG_decode == null, PNG_error=%d", PNG_error); return NULL; } NewImage = egCreateImage((INTN)info->width, (INTN)info->height, WantAlpha); if (NewImage == NULL) { // DBG("egCreateImage == null"); return NULL; } CopyMem(NewImage->PixelData, info->image->data, info->image->size); png_alloc_free_all(); Pixel = (EG_PIXEL*)NewImage->PixelData; for (y = 0; y < NewImage->Height; y++) { for (x = 0; x < NewImage->Width; x++) { UINT8 Temp; Temp = Pixel->b; Pixel->b = Pixel->r; Pixel->r = Temp; Pixel++; } } // DBG("png decoded %dx%d datalenght=%d iconsize=%d\n", NewImage->Height, NewImage->Width, FileDataLength, IconSize); return NewImage; } #endif //LODEPNG