Aditya Barve
This is a code which generates the various zoomed versions of an image stored in an SD card and displays it on a Nokia LCD based on the keys pressed on a capacitive touch pad.
Dependencies: FatFileSystem mbed
Fork of
Lab3
by 
Martin Sturm
Diff: picojpeg/picojpeg.c
- Revision:
- 1:6048138606a0
- Parent:
- 0:c546b51ecf0b
--- a/picojpeg/picojpeg.c Tue Oct 11 01:24:18 2011 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,1736 +0,0 @@
-//------------------------------------------------------------------------------
-// picojpeg v1.0 - Public domain, Rich Geldreich <richgel99@gmail.com>
-// Last modified Nov. 27, 2010
-//------------------------------------------------------------------------------
-#include "picojpeg.h"
-//------------------------------------------------------------------------------
-typedef unsigned char uint8;
-typedef unsigned short uint16;
-typedef signed char int8;
-typedef signed short int16;
-//------------------------------------------------------------------------------
-// Change as needed - the PJPG_MAX_WIDTH/PJPG_MAX_HEIGHT checks are only present
-// to quickly detect bogus files.
-#define PJPG_MAX_WIDTH 16384
-#define PJPG_MAX_HEIGHT 16384
-
-#define PJPG_MAXCOMPSINSCAN 3
-//------------------------------------------------------------------------------
-typedef enum
-{
- M_SOF0 = 0xC0,
- M_SOF1 = 0xC1,
- M_SOF2 = 0xC2,
- M_SOF3 = 0xC3,
-
- M_SOF5 = 0xC5,
- M_SOF6 = 0xC6,
- M_SOF7 = 0xC7,
-
- M_JPG = 0xC8,
- M_SOF9 = 0xC9,
- M_SOF10 = 0xCA,
- M_SOF11 = 0xCB,
-
- M_SOF13 = 0xCD,
- M_SOF14 = 0xCE,
- M_SOF15 = 0xCF,
-
- M_DHT = 0xC4,
-
- M_DAC = 0xCC,
-
- M_RST0 = 0xD0,
- M_RST1 = 0xD1,
- M_RST2 = 0xD2,
- M_RST3 = 0xD3,
- M_RST4 = 0xD4,
- M_RST5 = 0xD5,
- M_RST6 = 0xD6,
- M_RST7 = 0xD7,
-
- M_SOI = 0xD8,
- M_EOI = 0xD9,
- M_SOS = 0xDA,
- M_DQT = 0xDB,
- M_DNL = 0xDC,
- M_DRI = 0xDD,
- M_DHP = 0xDE,
- M_EXP = 0xDF,
-
- M_APP0 = 0xE0,
- M_APP15 = 0xEF,
-
- M_JPG0 = 0xF0,
- M_JPG13 = 0xFD,
- M_COM = 0xFE,
-
- M_TEM = 0x01,
-
- M_ERROR = 0x100
-} JPEG_MARKER;
-
-#define RST0 0xD0
-//------------------------------------------------------------------------------
-const int8 ZAG[] =
-{
- 0, 1, 8, 16, 9, 2, 3, 10,
- 17, 24, 32, 25, 18, 11, 4, 5,
- 12, 19, 26, 33, 40, 48, 41, 34,
- 27, 20, 13, 6, 7, 14, 21, 28,
- 35, 42, 49, 56, 57, 50, 43, 36,
- 29, 22, 15, 23, 30, 37, 44, 51,
- 58, 59, 52, 45, 38, 31, 39, 46,
- 53, 60, 61, 54, 47, 55, 62, 63,
-};
-//------------------------------------------------------------------------------
-// 128 bytes
-static int16 gCoeffBuf[8*8];
-
-// 8*8*4 bytes * 3 = 768
-static uint8 gMCUBufR[256];
-static uint8 gMCUBufG[256];
-static uint8 gMCUBufB[256];
-
-// 256 bytes
-static int16 gQuant0[8*8];
-static int16 gQuant1[8*8];
-
-// 6 bytes
-static int16 gLastDC[3];
-
-typedef struct HuffTableT
-{
- uint16 mMinCode[16];
- uint16 mMaxCode[16];
- uint8 mValPtr[16];
-} HuffTable;
-
-// DC - 192
-static HuffTable gHuffTab0;
-
-static uint8 gHuffVal0[16];
-
-static HuffTable gHuffTab1;
-static uint8 gHuffVal1[16];
-
-// AC - 672
-static HuffTable gHuffTab2;
-static uint8 gHuffVal2[256];
-
-static HuffTable gHuffTab3;
-static uint8 gHuffVal3[256];
-
-static uint8 gValidHuffTables;
-static uint8 gValidQuantTables;
-
-static uint8 gTemFlag;
-#define MAX_IN_BUF_SIZE 256
-static uint8 gInBuf[MAX_IN_BUF_SIZE];
-static uint8 gInBufOfs;
-static uint8 gInBufLeft;
-
-static uint16 gBitBuf;
-static uint8 gBitsLeft;
-//------------------------------------------------------------------------------
-static uint16 gImageXSize;
-static uint16 gImageYSize;
-static uint8 gCompsInFrame;
-static uint8 gCompIdent[3];
-static uint8 gCompHSamp[3];
-static uint8 gCompVSamp[3];
-static uint8 gCompQuant[3];
-
-static uint16 gRestartInterval;
-static uint16 gNextRestartNum;
-static uint16 gRestartsLeft;
-
-static uint8 gCompsInScan;
-static uint8 gCompList[3];
-static uint8 gCompDCTab[3]; // 0,1
-static uint8 gCompACTab[3]; // 0,1
-
-static pjpeg_scan_type_t gScanType;
-
-static uint8 gMaxBlocksPerMCU;
-static uint8 gMaxMCUXSize;
-static uint8 gMaxMCUYSize;
-static uint16 gMaxMCUSPerRow;
-static uint16 gMaxMCUSPerCol;
-static uint16 gNumMCUSRemaining;
-static uint8 gMCUOrg[6];
-
-static pjpeg_need_bytes_callback_t g_pNeedBytesCallback;
-static void *g_pCallback_data;
-//------------------------------------------------------------------------------
-static uint8 fillInBuf(void)
-{
- unsigned char status;
-
- // Reserve a few bytes at the beginning of the buffer for putting back ("stuffing") chars.
- gInBufOfs = 4;
- gInBufLeft = 0;
-
- status = (*g_pNeedBytesCallback)(gInBuf + gInBufOfs, MAX_IN_BUF_SIZE - gInBufOfs, &gInBufLeft, g_pCallback_data);
- if (status)
- return status;
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 getChar(void)
-{
- if (!gInBufLeft)
- {
- fillInBuf();
- if (!gInBufLeft)
- {
- gTemFlag = ~gTemFlag;
- return gTemFlag ? 0xFF : 0xD9;
- }
- }
-
- gInBufLeft--;
- return gInBuf[gInBufOfs++];
-}
-//------------------------------------------------------------------------------
-static void stuffChar(uint8 i)
-{
- gInBufOfs--;
- gInBuf[gInBufOfs] = i;
- gInBufLeft++;
-}
-//------------------------------------------------------------------------------
-static uint8 getOctet(uint8 FFCheck)
-{
- uint8 c = getChar();
-
- if ((FFCheck) && (c == 0xFF))
- {
- uint8 n = getChar();
-
- if (n)
- {
- stuffChar(n);
- stuffChar(0xFF);
- }
- }
-
- return c;
-}
-//------------------------------------------------------------------------------
-static uint16 getBits(uint8 numBits, uint8 FFCheck)
-{
- uint8 origBits = numBits;
- uint16 ret = gBitBuf;
-
- if (numBits > 8)
- {
- numBits -= 8;
-
- gBitBuf <<= gBitsLeft;
-
- gBitBuf |= getOctet(FFCheck);
-
- gBitBuf <<= (8 - gBitsLeft);
-
- ret = (ret & 0xFF00) | (gBitBuf >> 8);
- }
-
- if (gBitsLeft < numBits)
- {
- gBitBuf <<= gBitsLeft;
-
- gBitBuf |= getOctet(FFCheck);
-
- gBitBuf <<= (numBits - gBitsLeft);
-
- gBitsLeft = 8 - (numBits - gBitsLeft);
- }
- else
- {
- gBitsLeft = (uint8)(gBitsLeft - numBits);
- gBitBuf <<= numBits;
- }
-
- return ret >> (16 - origBits);
-}
-//------------------------------------------------------------------------------
-static uint16 getBits1(uint8 numBits)
-{
- return getBits(numBits, 0);
-}
-//------------------------------------------------------------------------------
-static uint16 getBits2(uint8 numBits)
-{
- return getBits(numBits, 1);
-}
-//------------------------------------------------------------------------------
-static uint8 getBit(void)
-{
- uint8 ret = 0;
- if (gBitBuf & 0x8000)
- ret = 1;
-
- if (!gBitsLeft)
- {
- gBitBuf |= getOctet(1);
-
- gBitsLeft += 8;
- }
-
- gBitsLeft--;
- gBitBuf <<= 1;
-
- return ret;
-}
-//------------------------------------------------------------------------------
-static uint16 getExtendTest(uint8 i)
-{
- switch (i)
- {
- case 0: return 0;
- case 1: return 0x0001;
- case 2: return 0x0002;
- case 3: return 0x0004;
- case 4: return 0x0008;
- case 5: return 0x0010;
- case 6: return 0x0020;
- case 7: return 0x0040;
- case 8: return 0x0080;
- case 9: return 0x0100;
- case 10: return 0x0200;
- case 11: return 0x0400;
- case 12: return 0x0800;
- case 13: return 0x1000;
- case 14: return 0x2000;
- case 15: return 0x4000;
- default: return 0;
- }
-}
-//------------------------------------------------------------------------------
-static int16 getExtendOffset(uint8 i)
-{
- switch (i)
- {
- case 0: return 0;
- case 1: return ((-1)<<1) + 1;
- case 2: return ((-1)<<2) + 1;
- case 3: return ((-1)<<3) + 1;
- case 4: return ((-1)<<4) + 1;
- case 5: return ((-1)<<5) + 1;
- case 6: return ((-1)<<6) + 1;
- case 7: return ((-1)<<7) + 1;
- case 8: return ((-1)<<8) + 1;
- case 9: return ((-1)<<9) + 1;
- case 10: return ((-1)<<10) + 1;
- case 11: return ((-1)<<11) + 1;
- case 12: return ((-1)<<12) + 1;
- case 13: return ((-1)<<13) + 1;
- case 14: return ((-1)<<14) + 1;
- case 15: return ((-1)<<15) + 1;
- default: return 0;
- }
-};
-//------------------------------------------------------------------------------
-static int16 huffExtend(uint16 x, uint8 s)
-{
- return ((x < getExtendTest(s)) ? ((int16)x + getExtendOffset(s)) : (int16)x);
-}
-//------------------------------------------------------------------------------
-static uint8 huffDecode(const HuffTable* pHuffTable, const uint8* pHuffVal)
-{
- uint8 i = 0;
- uint8 j;
- uint16 code = getBit();
-
- for ( ; ; )
- {
- uint16 maxCode;
-
- if (i == 16)
- return 0;
-
- maxCode = pHuffTable->mMaxCode[i];
- if ((code <= maxCode) && (maxCode != 0xFFFF))
- break;
-
- i++;
- code <<= 1;
- code |= getBit();
- }
-
- j = pHuffTable->mValPtr[i];
- j = (uint8)(j + (code - pHuffTable->mMinCode[i]));
-
- return pHuffVal[j];
-}
-//------------------------------------------------------------------------------
-static void huffCreate(const uint8* pBits, HuffTable* pHuffTable)
-{
- uint8 i = 0;
- uint8 j = 0;
-
- uint16 code = 0;
-
- for ( ; ; )
- {
- uint8 num = pBits[i];
-
- if (!num)
- {
- pHuffTable->mMinCode[i] = 0x0000;
- pHuffTable->mMaxCode[i] = 0xFFFF;
- pHuffTable->mValPtr[i] = 0;
- }
- else
- {
- pHuffTable->mMinCode[i] = code;
- pHuffTable->mMaxCode[i] = code + num - 1;
- pHuffTable->mValPtr[i] = j;
-
- j = (uint8)(j + num);
-
- code = (uint16)(code + num);
- }
-
- code <<= 1;
-
- i++;
- if (i > 15)
- break;
- }
-}
-//------------------------------------------------------------------------------
-static HuffTable* getHuffTable(uint8 index)
-{
- // 0-1 = DC
- // 2-3 = AC
- switch (index)
- {
- case 0: return &gHuffTab0;
- case 1: return &gHuffTab1;
- case 2: return &gHuffTab2;
- case 3: return &gHuffTab3;
- default: return 0;
- }
-}
-//------------------------------------------------------------------------------
-static uint8* getHuffVal(uint8 index)
-{
- // 0-1 = DC
- // 2-3 = AC
- switch (index)
- {
- case 0: return gHuffVal0;
- case 1: return gHuffVal1;
- case 2: return gHuffVal2;
- case 3: return gHuffVal3;
- default: return 0;
- }
-}
-//------------------------------------------------------------------------------
-static uint16 getMaxHuffCodes(uint8 index)
-{
- return (index < 2) ? 12 : 255;
-}
-//------------------------------------------------------------------------------
-static uint8 readDHTMarker(void)
-{
- uint8 bits[16];
- uint16 left = getBits1(16);
-
- if (left < 2)
- return PJPG_BAD_DHT_MARKER;
-
- left -= 2;
-
- while (left)
- {
- uint8 i, tableIndex, index;
- uint8* pHuffVal;
- HuffTable* pHuffTable;
- uint16 count, totalRead;
-
- index = (uint8)getBits1(8);
-
- if ( ((index & 0xF) > 1) || ((index & 0xF0) > 0x10) )
- return PJPG_BAD_DHT_INDEX;
-
- tableIndex = ((index >> 3) & 2) + (index & 1);
-
- pHuffTable = getHuffTable(tableIndex);
- pHuffVal = getHuffVal(tableIndex);
-
- gValidHuffTables |= (1 << tableIndex);
-
- count = 0;
- for (i = 0; i <= 15; i++)
- {
- uint8 n = (uint8)getBits1(8);
- bits[i] = n;
- count = (uint16)(count + n);
- }
-
- if (count > getMaxHuffCodes(tableIndex))
- return PJPG_BAD_DHT_COUNTS;
-
- for (i = 0; i < count; i++)
- pHuffVal[i] = (uint8)getBits1(8);
-
- totalRead = 1 + 16 + count;
-
- if (left < totalRead)
- return PJPG_BAD_DHT_MARKER;
-
- left = (uint16)(left - totalRead);
-
- huffCreate(bits, pHuffTable);
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static void createWinogradQuant(int16* pQuant);
-
-static uint8 readDQTMarker(void)
-{
- uint16 left = getBits1(16);
-
- if (left < 2)
- return PJPG_BAD_DQT_MARKER;
-
- left -= 2;
-
- while (left)
- {
- uint8 i;
- uint8 n = (uint8)getBits1(8);
- uint8 prec = n >> 4;
- uint16 totalRead;
-
- n &= 0x0F;
-
- if (n > 1)
- return PJPG_BAD_DQT_TABLE;
-
- gValidQuantTables |= (n ? 2 : 1);
-
- // read quantization entries, in zag order
- for (i = 0; i < 64; i++)
- {
- uint16 temp = getBits1(8);
-
- if (prec)
- temp = (temp << 8) + getBits1(8);
-
- if (n)
- gQuant1[i] = (int16)temp;
- else
- gQuant0[i] = (int16)temp;
- }
-
- createWinogradQuant(n ? gQuant1 : gQuant0);
-
- totalRead = 64 + 1;
-
- if (prec)
- totalRead += 64;
-
- if (left < totalRead)
- return PJPG_BAD_DQT_LENGTH;
-
- left = (uint16)(left - totalRead);
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 readSOFMarker(void)
-{
- uint8 i;
- uint16 left = getBits1(16);
-
- if (getBits1(8) != 8)
- return PJPG_BAD_PRECISION;
-
- gImageYSize = getBits1(16);
-
- if ((!gImageYSize) || (gImageYSize > PJPG_MAX_HEIGHT))
- return PJPG_BAD_HEIGHT;
-
- gImageXSize = getBits1(16);
-
- if ((!gImageXSize) || (gImageXSize > PJPG_MAX_WIDTH))
- return PJPG_BAD_WIDTH;
-
- gCompsInFrame = (uint8)getBits1(8);
-
- if (gCompsInFrame > 3)
- return PJPG_TOO_MANY_COMPONENTS;
-
- if (left != (gCompsInFrame + gCompsInFrame + gCompsInFrame + 8))
- return PJPG_BAD_SOF_LENGTH;
-
- for (i = 0; i < gCompsInFrame; i++)
- {
- gCompIdent[i] = (uint8)getBits1(8);
- gCompHSamp[i] = (uint8)getBits1(4);
- gCompVSamp[i] = (uint8)getBits1(4);
- gCompQuant[i] = (uint8)getBits1(8);
-
- if (gCompQuant[i] > 1)
- return PJPG_UNSUPPORTED_QUANT_TABLE;
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-// Used to skip unrecognized markers.
-static uint8 skipVariableMarker(void)
-{
- uint16 left = getBits1(16);
-
- if (left < 2)
- return PJPG_BAD_VARIABLE_MARKER;
-
- left -= 2;
-
- while (left)
- {
- getBits1(8);
- left--;
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-// Read a define restart interval (DRI) marker.
-static uint8 readDRIMarker(void)
-{
- if (getBits1(16) != 4)
- return PJPG_BAD_DRI_LENGTH;
-
- gRestartInterval = getBits1(16);
-
- return 0;
-}
-//------------------------------------------------------------------------------
-// Read a start of scan (SOS) marker.
-static uint8 readSOSMarker(void)
-{
- uint8 i;
- uint16 left = getBits1(16);
- uint8 spectral_start, spectral_end, successive_high, successive_low;
-
- gCompsInScan = (uint8)getBits1(8);
-
- left -= 3;
-
- if ( (left != (gCompsInScan + gCompsInScan + 3)) || (gCompsInScan < 1) || (gCompsInScan > PJPG_MAXCOMPSINSCAN) )
- return PJPG_BAD_SOS_LENGTH;
-
- for (i = 0; i < gCompsInScan; i++)
- {
- uint8 cc = (uint8)getBits1(8);
- uint8 c = (uint8)getBits1(8);
- uint8 ci;
-
- left -= 2;
-
- for (ci = 0; ci < gCompsInFrame; ci++)
- if (cc == gCompIdent[ci])
- break;
-
- if (ci >= gCompsInFrame)
- return PJPG_BAD_SOS_COMP_ID;
-
- gCompList[i] = ci;
- gCompDCTab[ci] = (c >> 4) & 15;
- gCompACTab[ci] = (c & 15);
- }
-
- spectral_start = (uint8)getBits1(8);
- spectral_end = (uint8)getBits1(8);
- successive_high = (uint8)getBits1(4);
- successive_low = (uint8)getBits1(4);
-
- left -= 3;
-
- while (left)
- {
- getBits1(8);
- left--;
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 nextMarker(void)
-{
- uint8 c;
- uint8 bytes = 0;
-
- do
- {
- do
- {
- bytes++;
-
- c = (uint8)getBits1(8);
-
- } while (c != 0xFF);
-
- do
- {
- c = (uint8)getBits1(8);
-
- } while (c == 0xFF);
-
- } while (c == 0);
-
- // If bytes > 0 here, there where extra bytes before the marker (not good).
-
- return c;
-}
-//------------------------------------------------------------------------------
-// Process markers. Returns when an SOFx, SOI, EOI, or SOS marker is
-// encountered.
-static uint8 processMarkers(uint8* pMarker)
-{
- for ( ; ; )
- {
- uint8 c = nextMarker();
-
- switch (c)
- {
- case M_SOF0:
- case M_SOF1:
- case M_SOF2:
- case M_SOF3:
- case M_SOF5:
- case M_SOF6:
- case M_SOF7:
- // case M_JPG:
- case M_SOF9:
- case M_SOF10:
- case M_SOF11:
- case M_SOF13:
- case M_SOF14:
- case M_SOF15:
- case M_SOI:
- case M_EOI:
- case M_SOS:
- {
- *pMarker = c;
- return 0;
- }
- case M_DHT:
- {
- readDHTMarker();
- break;
- }
- // Sorry, no arithmitic support at this time. Dumb patents!
- case M_DAC:
- {
- return PJPG_NO_ARITHMITIC_SUPPORT;
- }
- case M_DQT:
- {
- readDQTMarker();
- break;
- }
- case M_DRI:
- {
- readDRIMarker();
- break;
- }
- //case M_APP0: /* no need to read the JFIF marker */
-
- case M_JPG:
- case M_RST0: /* no parameters */
- case M_RST1:
- case M_RST2:
- case M_RST3:
- case M_RST4:
- case M_RST5:
- case M_RST6:
- case M_RST7:
- case M_TEM:
- {
- return PJPG_UNEXPECTED_MARKER;
- }
- default: /* must be DNL, DHP, EXP, APPn, JPGn, COM, or RESn or APP0 */
- {
- skipVariableMarker();
- break;
- }
- }
- }
-// return 0;
-}
-//------------------------------------------------------------------------------
-// Finds the start of image (SOI) marker.
-static uint8 locateSOIMarker(void)
-{
- uint16 bytesleft;
-
- uint8 lastchar = (uint8)getBits1(8);
-
- uint8 thischar = (uint8)getBits1(8);
-
- /* ok if it's a normal JPEG file without a special header */
-
- if ((lastchar == 0xFF) && (thischar == M_SOI))
- return 0;
-
- bytesleft = 4096; //512;
-
- for ( ; ; )
- {
- if (--bytesleft == 0)
- return PJPG_NOT_JPEG;
-
- lastchar = thischar;
-
- thischar = (uint8)getBits1(8);
-
- if (lastchar == 0xFF)
- {
- if (thischar == M_SOI)
- break;
- else if (thischar == M_EOI) //getBits1 will keep returning M_EOI if we read past the end
- return PJPG_NOT_JPEG;
- }
- }
-
- /* Check the next character after marker: if it's not 0xFF, it can't
- be the start of the next marker, so the file is bad */
-
- thischar = (uint8)((gBitBuf >> 8) & 0xFF);
-
- if (thischar != 0xFF)
- return PJPG_NOT_JPEG;
-
- return 0;
-}
-//------------------------------------------------------------------------------
-// Find a start of frame (SOF) marker.
-static uint8 locateSOFMarker(void)
-{
- uint8 c;
-
- uint8 status = locateSOIMarker();
- if (status)
- return status;
-
- status = processMarkers(&c);
- if (status)
- return status;
-
- switch (c)
- {
- case M_SOF2:
- {
- return PJPG_UNSUPPORTED_MODE;
- }
- case M_SOF0: /* baseline DCT */
- {
- status = readSOFMarker();
- if (status)
- return status;
-
- break;
- }
- case M_SOF9:
- {
- return PJPG_NO_ARITHMITIC_SUPPORT;
- }
- case M_SOF1: /* extended sequential DCT */
- default:
- {
- return PJPG_UNSUPPORTED_MARKER;
- }
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-// Find a start of scan (SOS) marker.
-static uint8 locateSOSMarker(uint8* pFoundEOI)
-{
- uint8 c;
- uint8 status;
-
- *pFoundEOI = 0;
-
- status = processMarkers(&c);
- if (status)
- return status;
-
- if (c == M_EOI)
- {
- *pFoundEOI = 1;
- return 0;
- }
- else if (c != M_SOS)
- return PJPG_UNEXPECTED_MARKER;
-
- return readSOSMarker();
-}
-//------------------------------------------------------------------------------
-static uint8 init(void)
-{
- gImageXSize = 0;
- gImageYSize = 0;
- gCompsInFrame = 0;
- gRestartInterval = 0;
- gCompsInScan = 0;
- gValidHuffTables = 0;
- gValidQuantTables = 0;
- gTemFlag = 0;
- gInBufOfs = 0;
- gInBufLeft = 0;
- gBitBuf = 0;
- gBitsLeft = 8;
-
- getBits1(8);
- getBits1(8);
-
- return 0;
-}
-//------------------------------------------------------------------------------
-// This method throws back into the stream any bytes that where read
-// into the bit buffer during initial marker scanning.
-static void fixInBuffer(void)
-{
- /* In case any 0xFF's where pulled into the buffer during marker scanning */
-
- if (gBitsLeft > 0)
- stuffChar((uint8)gBitBuf);
-
- stuffChar((uint8)(gBitBuf >> 8));
-
- gBitsLeft = 8;
- getBits2(8);
- getBits2(8);
-}
-//------------------------------------------------------------------------------
-// Restart interval processing.
-static uint8 processRestart(void)
-{
- // Let's scan a little bit to find the marker, but not _too_ far.
- // 1536 is a "fudge factor" that determines how much to scan.
- uint16 i;
- uint8 c = 0;
-
- for (i = 1536; i > 0; i--)
- if (getChar() == 0xFF)
- break;
-
- if (i == 0)
- return PJPG_BAD_RESTART_MARKER;
-
- for ( ; i > 0; i--)
- if ((c = getChar()) != 0xFF)
- break;
-
- if (i == 0)
- return PJPG_BAD_RESTART_MARKER;
-
- // Is it the expected marker? If not, something bad happened.
- if (c != (gNextRestartNum + M_RST0))
- return PJPG_BAD_RESTART_MARKER;
-
- // Reset each component's DC prediction values.
- gLastDC[0] = 0;
- gLastDC[1] = 0;
- gLastDC[2] = 0;
-
- gRestartsLeft = gRestartInterval;
-
- gNextRestartNum = (gNextRestartNum + 1) & 7;
-
- // Get the bit buffer going again...
-
- gBitsLeft = 8;
- getBits2(8);
- getBits2(8);
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 findEOI(void)
-{
- uint8 c;
- uint8 status;
-
- // Prime the bit buffer
- gBitsLeft = 8;
- getBits1(8);
- getBits1(8);
-
- // The next marker _should_ be EOI
- status = processMarkers(&c);
- if (status)
- return status;
-
- //gTotalBytesRead -= in_buf_left;
- if (c != M_EOI)
- return PJPG_UNEXPECTED_MARKER;
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 checkHuffTables(void)
-{
- uint8 i;
-
- for (i = 0; i < gCompsInScan; i++)
- {
- uint8 compDCTab = gCompDCTab[gCompList[i]];
- uint8 compACTab = gCompACTab[gCompList[i]] + 2;
-
- if ( ((gValidHuffTables & (1 << compDCTab)) == 0) ||
- ((gValidHuffTables & (1 << compACTab)) == 0) )
- return PJPG_UNDEFINED_HUFF_TABLE;
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 checkQuantTables(void)
-{
- uint8 i;
-
- for (i = 0; i < gCompsInScan; i++)
- {
- uint8 compQuantMask = gCompQuant[gCompList[i]] ? 2 : 1;
-
- if ((gValidQuantTables & compQuantMask) == 0)
- return PJPG_UNDEFINED_QUANT_TABLE;
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 initScan(void)
-{
- uint8 foundEOI;
- uint8 status = locateSOSMarker(&foundEOI);
- if (status)
- return status;
- if (foundEOI)
- return PJPG_UNEXPECTED_MARKER;
-
- status = checkHuffTables();
- if (status)
- return status;
-
- status = checkQuantTables();
- if (status)
- return status;
-
- gLastDC[0] = 0;
- gLastDC[1] = 0;
- gLastDC[2] = 0;
-
- if (gRestartInterval)
- {
- gRestartsLeft = gRestartInterval;
- gNextRestartNum = 0;
- }
-
- fixInBuffer();
-
- return 0;
-}
-//------------------------------------------------------------------------------
-static uint8 initFrame(void)
-{
- if (gCompsInFrame == 1)
- {
- if ((gCompHSamp[0] != 1) || (gCompVSamp[0] != 1))
- return PJPG_UNSUPPORTED_SAMP_FACTORS;
-
- gScanType = PJPG_GRAYSCALE;
-
- gMaxBlocksPerMCU = 1;
- gMCUOrg[0] = 0;
-
- gMaxMCUXSize = 8;
- gMaxMCUYSize = 8;
- }
- else if (gCompsInFrame == 3)
- {
- if ( ((gCompHSamp[1] != 1) || (gCompVSamp[1] != 1)) ||
- ((gCompHSamp[2] != 1) || (gCompVSamp[2] != 1)) )
- return PJPG_UNSUPPORTED_SAMP_FACTORS;
-
- if ((gCompHSamp[0] == 1) && (gCompVSamp[0] == 1))
- {
- gScanType = PJPG_YH1V1;
-
- gMaxBlocksPerMCU = 3;
- gMCUOrg[0] = 0;
- gMCUOrg[1] = 1;
- gMCUOrg[2] = 2;
-
- gMaxMCUXSize = 8;
- gMaxMCUYSize = 8;
- }
- else if ((gCompHSamp[0] == 2) && (gCompVSamp[0] == 2))
- {
- gScanType = PJPG_YH2V2;
-
- gMaxBlocksPerMCU = 6;
- gMCUOrg[0] = 0;
- gMCUOrg[1] = 0;
- gMCUOrg[2] = 0;
- gMCUOrg[3] = 0;
- gMCUOrg[4] = 1;
- gMCUOrg[5] = 2;
-
- gMaxMCUXSize = 16;
- gMaxMCUYSize = 16;
- }
- else
- return PJPG_UNSUPPORTED_SAMP_FACTORS;
- }
- else
- return PJPG_UNSUPPORTED_COLORSPACE;
-
- gMaxMCUSPerRow = (gImageXSize + (gMaxMCUXSize - 1)) >> ((gMaxMCUXSize == 8) ? 3 : 4);
- gMaxMCUSPerCol = (gImageYSize + (gMaxMCUYSize - 1)) >> ((gMaxMCUYSize == 8) ? 3 : 4);
-
- gNumMCUSRemaining = gMaxMCUSPerRow * gMaxMCUSPerCol;
-
- return 0;
-}
-/*----------------------------------------------------------------------------*/
-#define DCT_SCALE_BITS 7
-
-#define DCT_SCALE (1U << DCT_SCALE_BITS)
-
-#define DESCALE(x) (((x) + (1U << (DCT_SCALE_BITS - 1))) >> DCT_SCALE_BITS)
-
-#define WFIX(x) ((x) * DCT_SCALE + 0.5f)
-
-#define WINOGRAD_QUANT_SCALE_BITS 10
-
-const uint8 gWinogradQuant[] =
-{
- 128, 178, 178, 167, 246, 167, 151, 232,
- 232, 151, 128, 209, 219, 209, 128, 101,
- 178, 197, 197, 178, 101, 69, 139, 167,
- 177, 167, 139, 69, 35, 96, 131, 151,
- 151, 131, 96, 35, 49, 91, 118, 128,
- 118, 91, 49, 46, 81, 101, 101, 81,
- 46, 42, 69, 79, 69, 42, 35, 54,
- 54, 35, 28, 37, 28, 19, 19, 10,
-};
-
-static void createWinogradQuant(int16* pQuant)
-{
- uint8 i;
-
- for (i = 0; i < 64; i++)
- {
- long x = pQuant[i];
- x *= gWinogradQuant[i];
- pQuant[i] = (int16)((x + (1 << (WINOGRAD_QUANT_SCALE_BITS - DCT_SCALE_BITS - 1))) >> (WINOGRAD_QUANT_SCALE_BITS - DCT_SCALE_BITS));
- }
-}
-
-// 1/cos(4*pi/16)
-// 362, 256+106
-#define b1 362
-
-// 1/cos(6*pi/16)
-// 669, 256+256+157
-#define b2 669
-
-// 1/cos(4*pi/16)
-// 362, 256+106
-#define b3 362
-
-// 1/cos(2*pi/16)
-// 277, 256+21
-#define b4 277
-
-// 1/(cos(2*pi/16) + cos(6*pi/16))
-// 196, 196
-#define b5 196
-
-static int16 imul_b1_b3(int16 w)
-{
- long x = (w * 362L);
- x += 128L;
- return (int16)(x >> 8);
-}
-
-static int16 imul_b2(int16 w)
-{
- long x = (w * 669L);
- x += 128L;
- return (int16)(x >> 8);
-}
-
-static int16 imul_b4(int16 w)
-{
- long x = (w * 277L);
- x += 128L;
- return (int16)(x >> 8);
-}
-
-static int16 imul_b5(int16 w)
-{
- long x = (w * 196L);
- x += 128L;
- return (int16)(x >> 8);
-}
-
-static uint8 clamp(int16 s)
-{
- if ((uint16)s > 255U)
- {
- if (s < 0)
- return 0;
- else if (s > 255)
- return 255;
- }
-
- return (uint8)s;
-}
-
-static void idctRows(void)
-{
- uint8 i;
- int16* pSrc = gCoeffBuf;
-
- for (i = 0; i < 8; i++)
- {
- int16 src4 = *(pSrc+5);
- int16 src7 = *(pSrc+3);
- int16 x4 = src4 - src7;
- int16 x7 = src4 + src7;
-
- int16 src5 = *(pSrc+1);
- int16 src6 = *(pSrc+7);
- int16 x5 = src5 + src6;
- int16 x6 = src5 - src6;
-
- int16 tmp1 = imul_b5(x4 - x6);
- int16 stg26 = imul_b4(x6) - tmp1;
-
- int16 x24 = tmp1 - imul_b2(x4);
-
- int16 x15 = x5 - x7;
- int16 x17 = x5 + x7;
-
- int16 tmp2 = stg26 - x17;
- int16 tmp3 = imul_b1_b3(x15) - tmp2;
- int16 x44 = tmp3 + x24;
-
- int16 src0 = *(pSrc+0);
- int16 src1 = *(pSrc+4);
- int16 x30 = src0 + src1;
- int16 x31 = src0 - src1;
-
- int16 src2 = *(pSrc+2);
- int16 src3 = *(pSrc+6);
- int16 x12 = src2 - src3;
- int16 x13 = src2 + src3;
-
- int16 x32 = imul_b1_b3(x12) - x13;
-
- int16 x40 = x30 + x13;
- int16 x43 = x30 - x13;
- int16 x41 = x31 + x32;
- int16 x42 = x31 - x32;
-
- *(pSrc+0) = x40 + x17;
- *(pSrc+1) = x41 + tmp2;
- *(pSrc+2) = x42 + tmp3;
- *(pSrc+3) = x43 - x44;
- *(pSrc+4) = x43 + x44;
- *(pSrc+5) = x42 - tmp3;
- *(pSrc+6) = x41 - tmp2;
- *(pSrc+7) = x40 - x17;
-
- pSrc += 8;
- }
-}
-
-static void idctCols(void)
-{
- uint8 i;
-
- int16* pSrc = gCoeffBuf;
-
- for (i = 0; i < 8; i++)
- {
- int16 src4 = *(pSrc+5*8);
- int16 src7 = *(pSrc+3*8);
- int16 x4 = src4 - src7;
- int16 x7 = src4 + src7;
-
- int16 src5 = *(pSrc+1*8);
- int16 src6 = *(pSrc+7*8);
- int16 x5 = src5 + src6;
- int16 x6 = src5 - src6;
-
- int16 tmp1 = imul_b5(x4 - x6);
- int16 stg26 = imul_b4(x6) - tmp1;
-
- int16 x24 = tmp1 - imul_b2(x4);
-
- int16 x15 = x5 - x7;
- int16 x17 = x5 + x7;
-
- int16 tmp2 = stg26 - x17;
- int16 tmp3 = imul_b1_b3(x15) - tmp2;
- int16 x44 = tmp3 + x24;
-
- int16 src0 = *(pSrc+0*8);
- int16 src1 = *(pSrc+4*8);
- int16 x30 = src0 + src1;
- int16 x31 = src0 - src1;
-
- int16 src2 = *(pSrc+2*8);
- int16 src3 = *(pSrc+6*8);
- int16 x12 = src2 - src3;
- int16 x13 = src2 + src3;
-
- int16 x32 = imul_b1_b3(x12) - x13;
-
- int16 x40 = x30 + x13;
- int16 x43 = x30 - x13;
- int16 x41 = x31 + x32;
- int16 x42 = x31 - x32;
-
- *(pSrc+0*8) = clamp(DESCALE(x40 + x17) + 128);
- *(pSrc+1*8) = clamp(DESCALE(x41 + tmp2) + 128);
- *(pSrc+2*8) = clamp(DESCALE(x42 + tmp3) + 128);
- *(pSrc+3*8) = clamp(DESCALE(x43 - x44) + 128);
- *(pSrc+4*8) = clamp(DESCALE(x43 + x44) + 128);
- *(pSrc+5*8) = clamp(DESCALE(x42 - tmp3) + 128);
- *(pSrc+6*8) = clamp(DESCALE(x41 - tmp2) + 128);
- *(pSrc+7*8) = clamp(DESCALE(x40 - x17) + 128);
-
- pSrc++;
- }
-}
-
-/*----------------------------------------------------------------------------*/
-static uint8 addAndClamp(uint8 a, int16 b)
-{
- b = a + b;
-
- if ((uint16)b > 255U)
- {
- if (b < 0)
- return 0;
- else if (b > 255)
- return 255;
- }
-
- return (uint8)b;
-}
-/*----------------------------------------------------------------------------*/
-static uint8 subAndClamp(uint8 a, int16 b)
-{
- b = a - b;
-
- if ((uint16)b > 255U)
- {
- if (b < 0)
- return 0;
- else if (b > 255)
- return 255;
- }
-
- return (uint8)b;
-}
-/*----------------------------------------------------------------------------*/
-// 103/256
-//R = Y + 1.402 (Cr-128)
-
-// 88/256, 183/256
-//G = Y - 0.34414 (Cb-128) - 0.71414 (Cr-128)
-
-// 198/256
-//B = Y + 1.772 (Cb-128)
-/*----------------------------------------------------------------------------*/
-static void upsampleCb(uint8 srcOfs, uint8 dstOfs)
-{
- // Cb - affects G and B
- uint8 x, y;
- int16* pSrc = gCoeffBuf + srcOfs;
- uint8* pDstG = gMCUBufG + dstOfs;
- uint8* pDstB = gMCUBufB + dstOfs;
- for (y = 0; y < 4; y++)
- {
- for (x = 0; x < 4; x++)
- {
- uint8 cb = (uint8)*pSrc++;
- int16 cbG, cbB;
-
- cbG = ((cb * 88U) >> 8U) - 44U;
- pDstG[0] = subAndClamp(pDstG[0], cbG);
- pDstG[1] = subAndClamp(pDstG[1], cbG);
- pDstG[8] = subAndClamp(pDstG[8], cbG);
- pDstG[9] = subAndClamp(pDstG[9], cbG);
-
- cbB = (cb + ((cb * 198U) >> 8U)) - 227U;
- pDstB[0] = addAndClamp(pDstB[0], cbB);
- pDstB[1] = addAndClamp(pDstB[1], cbB);
- pDstB[8] = addAndClamp(pDstB[8], cbB);
- pDstB[9] = addAndClamp(pDstB[9], cbB);
-
- pDstG += 2;
- pDstB += 2;
- }
-
- pSrc = pSrc - 4 + 8;
- pDstG = pDstG - 8 + 16;
- pDstB = pDstB - 8 + 16;
- }
-}
-/*----------------------------------------------------------------------------*/
-// 103/256
-//R = Y + 1.402 (Cr-128)
-
-// 88/256, 183/256
-//G = Y - 0.34414 (Cb-128) - 0.71414 (Cr-128)
-
-// 198/256
-//B = Y + 1.772 (Cb-128)
-/*----------------------------------------------------------------------------*/
-static void upsampleCr(uint8 srcOfs, uint8 dstOfs)
-{
- // Cr - affects R and G
- uint8 x, y;
- int16* pSrc = gCoeffBuf + srcOfs;
- uint8* pDstR = gMCUBufR + dstOfs;
- uint8* pDstG = gMCUBufG + dstOfs;
- for (y = 0; y < 4; y++)
- {
- for (x = 0; x < 4; x++)
- {
- uint8 cr = (uint8)*pSrc++;
- int16 crR, crG;
-
- crR = (cr + ((cr * 103U) >> 8U)) - 179;
- pDstR[0] = addAndClamp(pDstR[0], crR);
- pDstR[1] = addAndClamp(pDstR[1], crR);
- pDstR[8] = addAndClamp(pDstR[8], crR);
- pDstR[9] = addAndClamp(pDstR[9], crR);
-
- crG = ((cr * 183U) >> 8U) - 91;
- pDstG[0] = subAndClamp(pDstG[0], crG);
- pDstG[1] = subAndClamp(pDstG[1], crG);
- pDstG[8] = subAndClamp(pDstG[8], crG);
- pDstG[9] = subAndClamp(pDstG[9], crG);
-
- pDstR += 2;
- pDstG += 2;
- }
-
- pSrc = pSrc - 4 + 8;
- pDstR = pDstR - 8 + 16;
- pDstG = pDstG - 8 + 16;
- }
-}
-/*----------------------------------------------------------------------------*/
-static void copyY(uint8 dstOfs)
-{
- uint8 i;
- uint8* pRDst = gMCUBufR + dstOfs;
- uint8* pGDst = gMCUBufG + dstOfs;
- uint8* pBDst = gMCUBufB + dstOfs;
- int16* pSrc = gCoeffBuf;
-
- for (i = 64; i > 0; i--)
- {
- uint8 c = (uint8)*pSrc++;
-
- *pRDst++ = c;
- *pGDst++ = c;
- *pBDst++ = c;
- }
-}
-/*----------------------------------------------------------------------------*/
-static void convertCb(uint8 dstOfs)
-{
- uint8 i;
- uint8* pDstG = gMCUBufG + dstOfs;
- uint8* pDstB = gMCUBufB + dstOfs;
- int16* pSrc = gCoeffBuf;
-
- for (i = 64; i > 0; i--)
- {
- uint8 cb = (uint8)*pSrc++;
- int16 cbG, cbB;
-
- cbG = ((cb * 88U) >> 8U) - 44U;
- *pDstG++ = subAndClamp(pDstG[0], cbG);
-
- cbB = (cb + ((cb * 198U) >> 8U)) - 227U;
- *pDstB++ = addAndClamp(pDstB[0], cbB);
- }
-}
-/*----------------------------------------------------------------------------*/
-static void convertCr(uint8 dstOfs)
-{
- uint8 i;
- uint8* pDstR = gMCUBufR + dstOfs;
- uint8* pDstG = gMCUBufG + dstOfs;
- int16* pSrc = gCoeffBuf;
-
- for (i = 64; i > 0; i--)
- {
- uint8 cr = (uint8)*pSrc++;
- int16 crR, crG;
-
- crR = (cr + ((cr * 103U) >> 8U)) - 179;
- *pDstR++ = addAndClamp(pDstR[0], crR);
-
- crG = ((cr * 183U) >> 8U) - 91;
- *pDstG++ = subAndClamp(pDstG[0], crG);
- }
-}
-/*----------------------------------------------------------------------------*/
-static void transformBlock(uint8 mcuBlock)
-{
- idctRows();
- idctCols();
-
- switch (gScanType)
- {
- case PJPG_GRAYSCALE:
- {
- copyY(0);
- break;
- }
- case PJPG_YH1V1:
- {
- switch (mcuBlock)
- {
- case 0:
- {
- copyY(0);
- break;
- }
- case 1:
- {
- convertCb(0);
- break;
- }
- case 2:
- {
- convertCr(0);
- break;
- }
- }
-
- break;
- }
- case PJPG_YH2V2:
- {
- switch (mcuBlock)
- {
- case 0:
- {
- copyY(0);
- break;
- }
- case 1:
- {
- copyY(64);
- break;
- }
- case 2:
- {
- copyY(128);
- break;
- }
- case 3:
- {
- copyY(192);
- break;
- }
- case 4:
- {
- upsampleCb(0, 0);
- upsampleCb(4, 64);
- upsampleCb(4*8, 128);
- upsampleCb(4+4*8, 192);
- break;
- }
- case 5:
- {
- upsampleCr(0, 0);
- upsampleCr(4, 64);
- upsampleCr(4*8, 128);
- upsampleCr(4+4*8, 192);
- break;
- }
- }
- }
- }
-}
-//------------------------------------------------------------------------------
-static uint8 decodeNextMCU(void)
-{
- uint8 status;
- uint8 mcuBlock;
-
- if (gRestartInterval)
- {
- if (gRestartsLeft == 0)
- {
- status = processRestart();
- if (status)
- return status;
- }
- gRestartsLeft--;
- }
-
- for (mcuBlock = 0; mcuBlock < gMaxBlocksPerMCU; mcuBlock++)
- {
- uint8 componentID = gMCUOrg[mcuBlock];
- uint8 compQuant = gCompQuant[componentID];
- uint8 compDCTab = gCompDCTab[componentID];
- uint8 numExtraBits, compACTab, k;
- const int16* pQ = compQuant ? gQuant1 : gQuant0;
- uint16 r, dc;
-
- uint8 s = huffDecode(compDCTab ? &gHuffTab1 : &gHuffTab0, compDCTab ? gHuffVal1 : gHuffVal0);
-
- r = 0;
- numExtraBits = s & 0xF;
- if (numExtraBits)
- r = getBits2(numExtraBits);
- dc = huffExtend(r, s);
-
- dc = dc + gLastDC[componentID];
- gLastDC[componentID] = dc;
-
- gCoeffBuf[0] = dc * pQ[0];
-
- compACTab = gCompACTab[componentID];
-
- for (k = 1; k < 64; k++)
- {
- uint16 extraBits;
-
- s = huffDecode(compACTab ? &gHuffTab3 : &gHuffTab2, compACTab ? gHuffVal3 : gHuffVal2);
-
- extraBits = 0;
- numExtraBits = s & 0xF;
- if (numExtraBits)
- extraBits = getBits2(numExtraBits);
-
- r = s >> 4;
- s &= 15;
-
- if (s)
- {
- int16 ac;
-
- if (r)
- {
- if ((k + r) > 63)
- return PJPG_DECODE_ERROR;
-
- while (r)
- {
- gCoeffBuf[ZAG[k++]] = 0;
- r--;
- }
- }
-
- ac = huffExtend(extraBits, s);
-
- gCoeffBuf[ZAG[k]] = ac * pQ[k];
- }
- else
- {
- if (r == 15)
- {
- if ((k + 16) > 64)
- return PJPG_DECODE_ERROR;
-
- for (r = 16; r > 0; r--)
- gCoeffBuf[ZAG[k++]] = 0;
-
- k--; // - 1 because the loop counter is k
- }
- else
- break;
- }
- }
-
- while (k < 64)
- gCoeffBuf[ZAG[k++]] = 0;
-
- transformBlock(mcuBlock);
- }
-
- return 0;
-}
-//------------------------------------------------------------------------------
-unsigned char pjpeg_decode_mcu(void)
-{
- uint8 status;
-
- if (!gNumMCUSRemaining)
- return PJPG_NO_MORE_BLOCKS;
-
- status = decodeNextMCU();
- if (status)
- return status;
-
- gNumMCUSRemaining--;
-
- return 0;
-}
-//------------------------------------------------------------------------------
-unsigned char pjpeg_decode_init(pjpeg_image_info_t *pInfo, pjpeg_need_bytes_callback_t pNeed_bytes_callback, void *pCallback_data)
-{
- uint8 status;
-
- g_pNeedBytesCallback = pNeed_bytes_callback;
- g_pCallback_data = pCallback_data;
-
- status = init();
- if (status)
- return status;
-
- status = locateSOFMarker();
- if (status)
- return status;
-
- status = initFrame();
- if (status)
- return status;
-
- status = initScan();
- if (status)
- return status;
-
- pInfo->m_width = gImageXSize;
- pInfo->m_height = gImageYSize;
- pInfo->m_comps = gCompsInFrame;
- pInfo->m_scanType = gScanType;
- pInfo->m_MCUSPerRow = gMaxMCUSPerRow;
- pInfo->m_MCUSPerCol = gMaxMCUSPerCol;
- pInfo->m_MCUWidth = gMaxMCUXSize;
- pInfo->m_MCUHeight = gMaxMCUYSize;
- pInfo->m_pMCUBufR = gMCUBufR;
- pInfo->m_pMCUBufG = gMCUBufG;
- pInfo->m_pMCUBufB = gMCUBufB;
-
- return 0;
-}