size_t enet_range_coder_compress (void * context, const ENetBuffer * inBuffers, size_t inBufferCount, size_t inLimit, enet_uint8 * outData, size_t outLimit) { ENetRangeCoder * rangeCoder = (ENetRangeCoder *) context; enet_uint8 * outStart = outData, * outEnd = & outData [outLimit]; const enet_uint8 * inData, * inEnd; enet_uint32 encodeLow = 0, encodeRange = ~0; ENetSymbol * root; enet_uint16 predicted = 0; size_t order = 0, nextSymbol = 0; if (rangeCoder == NULL || inBufferCount <= 0 || inLimit <= 0) return 0; inData = (const enet_uint8 *) inBuffers -> data; inEnd = & inData [inBuffers -> dataLength]; inBuffers ++; inBufferCount --; ENET_CONTEXT_CREATE (root, ENET_CONTEXT_ESCAPE_MINIMUM, ENET_CONTEXT_SYMBOL_MINIMUM); for (;;) { ENetSymbol * subcontext, * symbol; #ifdef ENET_CONTEXT_EXCLUSION const ENetSymbol * childContext = & emptyContext; #endif enet_uint8 value; enet_uint16 count, under, * parent = & predicted, total; if (inData >= inEnd) { if (inBufferCount <= 0) break; inData = (const enet_uint8 *) inBuffers -> data; inEnd = & inData [inBuffers -> dataLength]; inBuffers ++; inBufferCount --; } value = * inData ++; for (subcontext = & rangeCoder -> symbols [predicted]; subcontext != root; #ifdef ENET_CONTEXT_EXCLUSION childContext = subcontext, #endif subcontext = & rangeCoder -> symbols [subcontext -> parent]) { ENET_CONTEXT_ENCODE (subcontext, symbol, value, under, count, ENET_SUBCONTEXT_SYMBOL_DELTA, 0); * parent = symbol - rangeCoder -> symbols; parent = & symbol -> parent; total = subcontext -> total; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > ENET_SUBCONTEXT_SYMBOL_DELTA + ENET_SUBCONTEXT_ESCAPE_DELTA) ENET_CONTEXT_ENCODE_EXCLUDE (childContext, value, under, total, 0); #endif if (count > 0) { ENET_RANGE_CODER_ENCODE (subcontext -> escapes + under, count, total); } else { if (subcontext -> escapes > 0 && subcontext -> escapes < total) ENET_RANGE_CODER_ENCODE (0, subcontext -> escapes, total); subcontext -> escapes += ENET_SUBCONTEXT_ESCAPE_DELTA; subcontext -> total += ENET_SUBCONTEXT_ESCAPE_DELTA; } subcontext -> total += ENET_SUBCONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_SUBCONTEXT_SYMBOL_DELTA || subcontext -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (subcontext, 0); if (count > 0) goto nextInput; } ENET_CONTEXT_ENCODE (root, symbol, value, under, count, ENET_CONTEXT_SYMBOL_DELTA, ENET_CONTEXT_SYMBOL_MINIMUM); * parent = symbol - rangeCoder -> symbols; parent = & symbol -> parent; total = root -> total; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > ENET_SUBCONTEXT_SYMBOL_DELTA + ENET_SUBCONTEXT_ESCAPE_DELTA) ENET_CONTEXT_ENCODE_EXCLUDE (childContext, value, under, total, ENET_CONTEXT_SYMBOL_MINIMUM); #endif ENET_RANGE_CODER_ENCODE (root -> escapes + under, count, total); root -> total += ENET_CONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_CONTEXT_SYMBOL_DELTA + ENET_CONTEXT_SYMBOL_MINIMUM || root -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (root, ENET_CONTEXT_SYMBOL_MINIMUM); nextInput: if (order >= ENET_SUBCONTEXT_ORDER) predicted = rangeCoder -> symbols [predicted].parent; else order ++; ENET_RANGE_CODER_FREE_SYMBOLS; } ENET_RANGE_CODER_FLUSH; return (size_t) (outData - outStart); }
size_t enet_range_coder_decompress (void * context, const enet_uint8 * inData, size_t inLimit, enet_uint8 * outData, size_t outLimit) { ENetRangeCoder * rangeCoder = (ENetRangeCoder *) context; enet_uint8 * outStart = outData, * outEnd = & outData [outLimit]; const enet_uint8 * inEnd = & inData [inLimit]; enet_uint32 decodeLow = 0, decodeCode = 0, decodeRange = ~0; ENetSymbol * root; enet_uint16 predicted = 0; size_t order = 0, nextSymbol = 0; #ifdef ENET_CONTEXT_EXCLUSION ENetExclude excludes [256]; ENetExclude * nextExclude = excludes; #endif if (rangeCoder == NULL || inLimit <= 0) return 0; ENET_CONTEXT_CREATE (root, ENET_CONTEXT_ESCAPE_MINIMUM, ENET_CONTEXT_SYMBOL_MINIMUM); ENET_RANGE_CODER_SEED; for (;;) { ENetSymbol * subcontext, * symbol, * patch; #ifdef ENET_CONTEXT_EXCLUSION const ENetSymbol * childContext = & emptyContext; #endif enet_uint8 value = 0; enet_uint16 code, under, count, bottom, * parent = & predicted, total; for (subcontext = & rangeCoder -> symbols [predicted]; subcontext != root; #ifdef ENET_CONTEXT_EXCLUSION childContext = subcontext, #endif subcontext = & rangeCoder -> symbols [subcontext -> parent]) { if (subcontext -> escapes <= 0) continue; total = subcontext -> total; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > 0) ENET_CONTEXT_DECODE_EXCLUDE (childContext, total, 0); #endif if (subcontext -> escapes >= total) continue; code = ENET_RANGE_CODER_READ (total); if (code < subcontext -> escapes) { ENET_RANGE_CODER_DECODE (0, subcontext -> escapes, total); continue; } code -= subcontext -> escapes; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > 0) { ENET_CONTEXT_TRY_DECODE (subcontext, symbol, code, value, under, count, ENET_SUBCONTEXT_SYMBOL_DELTA, 0, ENET_CONTEXT_EXCLUDED); } else #endif { ENET_CONTEXT_TRY_DECODE (subcontext, symbol, code, value, under, count, ENET_SUBCONTEXT_SYMBOL_DELTA, 0, ENET_CONTEXT_NOT_EXCLUDED); } bottom = symbol - rangeCoder -> symbols; ENET_RANGE_CODER_DECODE (subcontext -> escapes + under, count, total); subcontext -> total += ENET_SUBCONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_SUBCONTEXT_SYMBOL_DELTA || subcontext -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (subcontext, 0); goto patchContexts; } total = root -> total; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > 0) ENET_CONTEXT_DECODE_EXCLUDE (childContext, total, ENET_CONTEXT_SYMBOL_MINIMUM); #endif code = ENET_RANGE_CODER_READ (total); if (code < root -> escapes) { ENET_RANGE_CODER_DECODE (0, root -> escapes, total); break; } code -= root -> escapes; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > 0) { ENET_CONTEXT_ROOT_DECODE (root, symbol, code, value, under, count, ENET_CONTEXT_SYMBOL_DELTA, ENET_CONTEXT_SYMBOL_MINIMUM, ENET_CONTEXT_EXCLUDED); } else #endif { ENET_CONTEXT_ROOT_DECODE (root, symbol, code, value, under, count, ENET_CONTEXT_SYMBOL_DELTA, ENET_CONTEXT_SYMBOL_MINIMUM, ENET_CONTEXT_NOT_EXCLUDED); } bottom = symbol - rangeCoder -> symbols; ENET_RANGE_CODER_DECODE (root -> escapes + under, count, total); root -> total += ENET_CONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_CONTEXT_SYMBOL_DELTA + ENET_CONTEXT_SYMBOL_MINIMUM || root -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (root, ENET_CONTEXT_SYMBOL_MINIMUM); patchContexts: for (patch = & rangeCoder -> symbols [predicted]; patch != subcontext; patch = & rangeCoder -> symbols [patch -> parent]) { ENET_CONTEXT_ENCODE (patch, symbol, value, under, count, ENET_SUBCONTEXT_SYMBOL_DELTA, 0); * parent = symbol - rangeCoder -> symbols; parent = & symbol -> parent; if (count <= 0) { patch -> escapes += ENET_SUBCONTEXT_ESCAPE_DELTA; patch -> total += ENET_SUBCONTEXT_ESCAPE_DELTA; } patch -> total += ENET_SUBCONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_SUBCONTEXT_SYMBOL_DELTA || patch -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (patch, 0); } * parent = bottom; ENET_RANGE_CODER_OUTPUT (value); if (order >= ENET_SUBCONTEXT_ORDER) predicted = rangeCoder -> symbols [predicted].parent; else order ++; ENET_RANGE_CODER_FREE_SYMBOLS; } return (size_t) (outData - outStart); }
size_t enet_range_coder_compress (void * context, const ENetBuffer * inBuffers, size_t inBufferCount, size_t inLimit, enet_uint8 * outData, size_t outLimit) { #ifdef _DEBUG //Seth - just some debug stuff to see how much this compresion was really doing.. not bad! // char stCrap[256]; // int inBuff = inLimit; #endif ENetRangeCoder * rangeCoder = (ENetRangeCoder *) context; enet_uint8 * outStart = outData, * outEnd = & outData [outLimit]; const enet_uint8 * inData, * inEnd; enet_uint32 encodeLow = 0, encodeRange = ~0; ENetSymbol * root; enet_uint16 predicted = 0; size_t order = 0, nextSymbol = 0; if (rangeCoder == NULL || inBufferCount <= 0 || inLimit <= 0) return 0; inData = (const enet_uint8 *) inBuffers -> data; inEnd = & inData [inBuffers -> dataLength]; inBuffers ++; inBufferCount --; ENET_CONTEXT_CREATE (root, ENET_CONTEXT_ESCAPE_MINIMUM, ENET_CONTEXT_SYMBOL_MINIMUM); for (;;) { ENetSymbol * subcontext, * symbol; #ifdef ENET_CONTEXT_EXCLUSION const ENetSymbol * childContext = & emptyContext; #endif enet_uint8 value; enet_uint16 count, under, * parent = & predicted, total; if (inData >= inEnd) { if (inBufferCount <= 0) break; inData = (const enet_uint8 *) inBuffers -> data; inEnd = & inData [inBuffers -> dataLength]; inBuffers ++; inBufferCount --; } value = * inData ++; for (subcontext = & rangeCoder -> symbols [predicted]; subcontext != root; #ifdef ENET_CONTEXT_EXCLUSION childContext = subcontext, #endif subcontext = & rangeCoder -> symbols [subcontext -> parent]) { ENET_CONTEXT_ENCODE (subcontext, symbol, value, under, count, ENET_SUBCONTEXT_SYMBOL_DELTA, 0); * parent = symbol - rangeCoder -> symbols; parent = & symbol -> parent; total = subcontext -> total; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > ENET_SUBCONTEXT_SYMBOL_DELTA + ENET_SUBCONTEXT_ESCAPE_DELTA) ENET_CONTEXT_ENCODE_EXCLUDE (childContext, value, under, total, 0); #endif if (count > 0) { ENET_RANGE_CODER_ENCODE (subcontext -> escapes + under, count, total); } else { if (subcontext -> escapes > 0 && subcontext -> escapes < total) ENET_RANGE_CODER_ENCODE (0, subcontext -> escapes, total); subcontext -> escapes += ENET_SUBCONTEXT_ESCAPE_DELTA; subcontext -> total += ENET_SUBCONTEXT_ESCAPE_DELTA; } subcontext -> total += ENET_SUBCONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_SUBCONTEXT_SYMBOL_DELTA || subcontext -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (subcontext, 0); if (count > 0) goto nextInput; } ENET_CONTEXT_ENCODE (root, symbol, value, under, count, ENET_CONTEXT_SYMBOL_DELTA, ENET_CONTEXT_SYMBOL_MINIMUM); * parent = symbol - rangeCoder -> symbols; parent = & symbol -> parent; total = root -> total; #ifdef ENET_CONTEXT_EXCLUSION if (childContext -> total > ENET_SUBCONTEXT_SYMBOL_DELTA + ENET_SUBCONTEXT_ESCAPE_DELTA) ENET_CONTEXT_ENCODE_EXCLUDE (childContext, value, under, total, ENET_CONTEXT_SYMBOL_MINIMUM); #endif ENET_RANGE_CODER_ENCODE (root -> escapes + under, count, total); root -> total += ENET_CONTEXT_SYMBOL_DELTA; if (count > 0xFF - 2*ENET_CONTEXT_SYMBOL_DELTA + ENET_CONTEXT_SYMBOL_MINIMUM || root -> total > ENET_RANGE_CODER_BOTTOM - 0x100) ENET_CONTEXT_RESCALE (root, ENET_CONTEXT_SYMBOL_MINIMUM); nextInput: if (order >= ENET_SUBCONTEXT_ORDER) predicted = rangeCoder -> symbols [predicted].parent; else order ++; ENET_RANGE_CODER_FREE_SYMBOLS; } ENET_RANGE_CODER_FLUSH; #ifdef _DEBUG // sprintf(stCrap, "in buffer count %d, compressed to %d\r\n", inBuff, (outData - outStart)); // OutputDebugString(stCrap); #endif g_enetTotalBytesSentDecompressed += inLimit; g_enetTotalBytesSent += outData - outStart; return (size_t) (outData - outStart); }