C++ DecoderState函数代码示例

int
TIFFInitLZW(TIFF* tif, int scheme)
{
	assert(scheme == COMPRESSION_LZW);
	/*
	 * Allocate state block so tag methods have storage to record values.
	 */
	tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LZWCodecState));
	if (tif->tif_data == NULL)
		goto bad;
	DecoderState(tif)->dec_codetab = NULL;
	DecoderState(tif)->dec_decode = NULL;
	EncoderState(tif)->enc_hashtab = NULL;
        LZWState(tif)->rw_mode = tif->tif_mode;

	/*
	 * Install codec methods.
	 */
	tif->tif_setupdecode = LZWSetupDecode;
	tif->tif_predecode = LZWPreDecode;
	tif->tif_decoderow = LZWDecode;
	tif->tif_decodestrip = LZWDecode;
	tif->tif_decodetile = LZWDecode;
	tif->tif_setupencode = LZWSetupEncode;
	tif->tif_preencode = LZWPreEncode;
	tif->tif_postencode = LZWPostEncode;
	tif->tif_encoderow = LZWEncode;
	tif->tif_encodestrip = LZWEncode;
	tif->tif_encodetile = LZWEncode;
	tif->tif_cleanup = LZWCleanup;
	/*
	 * Setup predictor setup.
	 */
	(void) TIFFPredictorInit(tif);
	return (1);
bad:
	TIFFErrorExt(tif->tif_clientdata, "TIFFInitLZW", 
		     "No space for LZW state block");
	return (0);
}

static int
ZIPSetupDecode(TIFF* tif)
{
	ZIPState* sp = DecoderState(tif);
	static char module[] = "ZIPSetupDecode";

	assert(sp != NULL);
	if (inflateInit2(&sp->stream, -DEF_WBITS) != Z_OK) {
		TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
		return (0);
	} else
		return (1);
}

static int
TWebPSetupDecode(TIFF* tif)
{
  static const char module[] = "WebPSetupDecode";
  uint16 nBitsPerSample = tif->tif_dir.td_bitspersample;
  uint16 sampleFormat = tif->tif_dir.td_sampleformat;

  WebPState* sp = DecoderState(tif);
  assert(sp != NULL);

  sp->nSamples = tif->tif_dir.td_samplesperpixel;

  /* check band count */
  if ( sp->nSamples != 3
#if WEBP_ENCODER_ABI_VERSION >= 0x0100
    && sp->nSamples != 4
#endif
  )
  {
    TIFFErrorExt(tif->tif_clientdata, module,
      "WEBP driver doesn't support %d bands. Must be 3 (RGB) "
  #if WEBP_ENCODER_ABI_VERSION >= 0x0100
      "or 4 (RGBA) "
  #endif
    "bands.",
    sp->nSamples );
    return 0;
  }

  /* check bits per sample and data type */
  if ((nBitsPerSample != 8) && (sampleFormat != 1)) {
    TIFFErrorExt(tif->tif_clientdata, module,
                "WEBP driver requires 8 bit unsigned data");
    return 0;
  }
  
  /* if we were last encoding, terminate this mode */
  if (sp->state & LSTATE_INIT_ENCODE) {
      WebPPictureFree(&sp->sPicture);
      if (sp->pBuffer != NULL) {
        _TIFFfree(sp->pBuffer);
        sp->pBuffer = NULL;
      }
      sp->buffer_offset = 0;
      sp->state = 0;
  }

  sp->state |= LSTATE_INIT_DECODE;

  return 1;
}

int
TIFFInitLZW(TIFF* tif, int scheme)
{
	assert(scheme == COMPRESSION_LZW);
	/*
	 * Allocate state block so tag methods have storage to record values.
	 */
	tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LZWDecodeState));
	if (tif->tif_data == NULL)
	  goto bad;
	if (tif->tif_mode == O_RDONLY) {
	  DecoderState(tif)->dec_codetab = NULL;
	  DecoderState(tif)->dec_decode = NULL;
	} 
	/*
	 * Install codec methods.
	 */
	tif->tif_setupdecode = LZWSetupDecode;
	tif->tif_predecode = LZWPreDecode;
	tif->tif_decoderow = LZWDecode;
	tif->tif_decodestrip = LZWDecode;
	tif->tif_decodetile = LZWDecode;
	tif->tif_setupencode = _LZWtrue; 
	tif->tif_preencode = _TIFFNoPreCode;
	tif->tif_postencode = _LZWtrue;
	tif->tif_encoderow = _TIFFNoRowEncode; 
	tif->tif_encodestrip = _TIFFNoStripEncode; 
	tif->tif_encodetile = _TIFFNoTileEncode; 
	tif->tif_cleanup = LZWCleanup;
	/*
	 * Setup predictor setup.
	 */
	(void) TIFFPredictorInit(tif);
	return (1);
bad:
	TIFFError("TIFFInitLZW", "No space for LZW state block");
	return (0);
}

static int
ZIPSetupDecode(TIFF* tif) {
    ZIPState* sp = DecoderState(tif);
    static const char module[] = "ZIPSetupDecode";

    assert(sp != NULL);
    if (inflateInit(&sp->stream) != Z_OK) {
        TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
        return (0);
    } else {
        sp->state |= ZSTATE_INIT;
        return (1);
    }
}

/*
 * Decode a string of 24-bit pixels.
 */
static int
LogLuvDecode24(TIFF* tif, uint8* op, tmsize_t occ, uint16 s)
{
	static const char module[] = "LogLuvDecode24";
	LogLuvState* sp = DecoderState(tif);
	tmsize_t cc;
	tmsize_t i;
	tmsize_t npixels;
	unsigned char* bp;
	uint32* tp;

	assert(s == 0);
	assert(sp != NULL);

	npixels = occ / sp->pixel_size;

	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
		tp = (uint32 *)op;
	else {
		assert(sp->tbuflen >= npixels);
		tp = (uint32 *) sp->tbuf;
	}
	/* copy to array of uint32 */
	bp = (unsigned char*) tif->tif_rawcp;
	cc = tif->tif_rawcc;
	for (i = 0; i < npixels && cc > 0; i++) {
		tp[i] = bp[0] << 16 | bp[1] << 8 | bp[2];
		bp += 3;
		cc -= 3;
	}
	tif->tif_rawcp = (uint8*) bp;
	tif->tif_rawcc = cc;
	if (i != npixels) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
		TIFFErrorExt(tif->tif_clientdata, module,
			"Not enough data at row %lu (short %I64d pixels)",
			     (unsigned long) tif->tif_row,
			     (unsigned __int64) (npixels - i));
#else
		TIFFErrorExt(tif->tif_clientdata, module,
			"Not enough data at row %lu (short %llu pixels)",
			     (unsigned long) tif->tif_row,
			     (unsigned long long) (npixels - i));
#endif
		return (0);
	}
	(*sp->tfunc)(sp, op, npixels);
	return (1);
}

/*
 * Setup state for decoding a strip.
 */
static int
ZIPPreDecode(TIFF* tif, tsample_t s)
{
	ZIPState* sp = DecoderState(tif);

	(void) s;
	assert(sp != NULL);

        if( (sp->state & ZSTATE_INIT_DECODE) == 0 )
            tif->tif_setupdecode( tif );

	sp->stream.next_in = tif->tif_rawdata;
	sp->stream.avail_in = tif->tif_rawcc;
	return (inflateReset(&sp->stream) == Z_OK);
}

static int
LERCSetupDecode(TIFF* tif)
{
        LERCState* sp = DecoderState(tif);

        assert(sp != NULL);

        /* if we were last encoding, terminate this mode */
        if (sp->state & LSTATE_INIT_ENCODE) {
            sp->state = 0;
        }

        sp->state |= LSTATE_INIT_DECODE;
        return 1;
}

static int
ZIPDecode(TIFF* tif, uint8* op, tmsize_t occ, uint16 s)
{
	static const char module[] = "ZIPDecode";
	ZIPState* sp = DecoderState(tif);

	(void) s;
	assert(sp != NULL);
	assert(sp->state == ZSTATE_INIT_DECODE);

	sp->stream.next_out = op;
	assert(sizeof(sp->stream.avail_out)==4);  /* if this assert gets raised,
	    we need to simplify this code to reflect a ZLib that is likely updated
	    to deal with 8byte memory sizes, though this code will respond
	    apropriately even before we simplify it */
	sp->stream.avail_out = (uInt) occ;
	if ((tmsize_t)sp->stream.avail_out != occ)
	{
		TIFFErrorExt(tif->tif_clientdata, module, "ZLib cannot deal with buffers this size");
		return (0);
	}
	do {
		int state = inflate(&sp->stream, Z_PARTIAL_FLUSH);
		if (state == Z_STREAM_END)
			break;
		if (state == Z_DATA_ERROR) {
			TIFFErrorExt(tif->tif_clientdata, module,
			    "Decoding error at scanline %lu, %s",
			    (unsigned long) tif->tif_row, sp->stream.msg);
			if (inflateSync(&sp->stream) != Z_OK)
				return (0);
			continue;
		}
		if (state != Z_OK) {
			TIFFErrorExt(tif->tif_clientdata, module, "ZLib error: %s",
			    sp->stream.msg);
			return (0);
		}
	} while (sp->stream.avail_out > 0);
	if (sp->stream.avail_out != 0) {
		TIFFErrorExt(tif->tif_clientdata, module,
		    "Not enough data at scanline %lu (short %llu bytes)",
		    (unsigned long) tif->tif_row, (unsigned long long) sp->stream.avail_out);
		return (0);
	}
	return (1);
}

static int
ZIPSetupDecode(TIFF* tif)
{
	ZIPState* sp = DecoderState(tif);
	static const char module[] = "ZIPSetupDecode";

	assert(sp != NULL);
        
        /* if we were last encoding, terminate this mode */
	if (sp->state & ZSTATE_INIT_ENCODE) {
            deflateEnd(&sp->stream);
            sp->state = 0;
        }

	if (inflateInit(&sp->stream) != Z_OK) {
		TIFFErrorExt(tif->tif_clientdata, module, "%s: %s", tif->tif_name, sp->stream.msg);
		return (0);
	} else {
		sp->state |= ZSTATE_INIT_DECODE;
		return (1);
	}
}

/*
 * Decode a string of 24-bit pixels.
 */
static int
LogLuvDecode24(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
{
	LogLuvState* sp = DecoderState(tif);
	int cc, i, npixels;
	u_char* bp;
	uint32* tp;

	assert(s == 0);
	assert(sp != NULL);

	npixels = occ / sp->pixel_size;

	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
		tp = (uint32 *)op;
	else {
		assert(sp->tbuflen >= npixels);
		tp = (uint32 *) sp->tbuf;
	}
	_TIFFmemset((tdata_t) tp, 0, npixels*sizeof (tp[0]));
					/* copy to array of uint32 */
	bp = (u_char*) tif->tif_rawcp;
	cc = tif->tif_rawcc;
	for (i = 0; i < npixels && cc > 0; i++) {
		tp[i] = bp[0] << 16 | bp[1] << 8 | bp[2];
		bp += 3;
		cc -= 3;
	}
	tif->tif_rawcp = (tidata_t) bp;
	tif->tif_rawcc = cc;
	if (i != npixels) {
		TIFFError(tif->tif_name,
	    "LogLuvDecode24: Not enough data at row %d (short %d pixels)",
		    tif->tif_row, npixels - i);
		return (0);
	}
	(*sp->tfunc)(sp, op, npixels);
	return (1);
}

static int
ZIPDecode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
{
	ZIPState* sp = DecoderState(tif);
	static const char module[] = "ZIPDecode";

	(void) s;
	assert(sp != NULL);
        assert(sp->state == ZSTATE_INIT_DECODE);

	sp->stream.next_out = op;
	sp->stream.avail_out = occ;
	do {
		int state = inflate(&sp->stream, Z_PARTIAL_FLUSH);
		if (state == Z_STREAM_END)
			break;
		if (state == Z_DATA_ERROR) {
			TIFFErrorExt(tif->tif_clientdata, module,
			    "%s: Decoding error at scanline %d, %s",
			    tif->tif_name, tif->tif_row, sp->stream.msg);
			if (inflateSync(&sp->stream) != Z_OK)
				return (0);
			continue;
		}
		if (state != Z_OK) {
			TIFFErrorExt(tif->tif_clientdata, module, "%s: zlib error: %s",
			    tif->tif_name, sp->stream.msg);
			return (0);
		}
	} while (sp->stream.avail_out > 0);
	if (sp->stream.avail_out != 0) {
		TIFFErrorExt(tif->tif_clientdata, module,
		    "%s: Not enough data at scanline %d (short %d bytes)",
		    tif->tif_name, tif->tif_row, sp->stream.avail_out);
		return (0);
	}
	return (1);
}

/*
 * Decode a string of 32-bit pixels.
 */
static int
LogLuvDecode32(TIFF* tif, uint8* op, tmsize_t occ, uint16 s)
{
	static const char module[] = "LogLuvDecode32";
	LogLuvState* sp;
	int shft;
	tmsize_t i;
	tmsize_t npixels;
	unsigned char* bp;
	uint32* tp;
	uint32 b;
	tmsize_t cc;
	int rc;

	assert(s == 0);
	sp = DecoderState(tif);
	assert(sp != NULL);

	npixels = occ / sp->pixel_size;

	if (sp->user_datafmt == SGILOGDATAFMT_RAW)
		tp = (uint32*) op;
	else {
		assert(sp->tbuflen >= npixels);
		tp = (uint32*) sp->tbuf;
	}
	_TIFFmemset((void*) tp, 0, npixels*sizeof (tp[0]));

	bp = (unsigned char*) tif->tif_rawcp;
	cc = tif->tif_rawcc;
	/* get each byte string */
	for (shft = 4*8; (shft -= 8) >= 0; ) {
		for (i = 0; i < npixels && cc > 0; )
			if (*bp >= 128) {		/* run */
				rc = *bp++ + (2-128);
				b = (uint32)*bp++ << shft;
				cc -= 2;                /* TODO: potential input buffer overrun when decoding corrupt or truncated data */
				while (rc-- && i < npixels)
					tp[i++] |= b;
			} else {			/* non-run */
				rc = *bp++;		/* nul is noop */
				while (--cc && rc-- && i < npixels)
					tp[i++] |= (uint32)*bp++ << shft;
			}
		if (i != npixels) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
			TIFFErrorExt(tif->tif_clientdata, module,
			"Not enough data at row %lu (short %I64d pixels)",
				     (unsigned long) tif->tif_row,
				     (unsigned __int64) (npixels - i));
#else
			TIFFErrorExt(tif->tif_clientdata, module,
			"Not enough data at row %lu (short %llu pixels)",
				     (unsigned long) tif->tif_row,
				     (unsigned long long) (npixels - i));
#endif
			tif->tif_rawcp = (uint8*) bp;
			tif->tif_rawcc = cc;
			return (0);
		}
	}
	(*sp->tfunc)(sp, op, npixels);
	tif->tif_rawcp = (uint8*) bp;
	tif->tif_rawcc = cc;
	return (1);
}

/*
 * Decode a string of 16-bit gray pixels.
 */
static int
LogL16Decode(TIFF* tif, uint8* op, tmsize_t occ, uint16 s)
{
	static const char module[] = "LogL16Decode";
	LogLuvState* sp = DecoderState(tif);
	int shft;
	tmsize_t i;
	tmsize_t npixels;
	unsigned char* bp;
	int16* tp;
	int16 b;
	tmsize_t cc;
	int rc;

	assert(s == 0);
	assert(sp != NULL);

	npixels = occ / sp->pixel_size;

	if (sp->user_datafmt == SGILOGDATAFMT_16BIT)
		tp = (int16*) op;
	else {
		if(sp->tbuflen < npixels) {
			TIFFErrorExt(tif->tif_clientdata, module,
						 "Translation buffer too short");
			return (0);
		}
		tp = (int16*) sp->tbuf;
	}
	_TIFFmemset((void*) tp, 0, npixels*sizeof (tp[0]));

	bp = (unsigned char*) tif->tif_rawcp;
	cc = tif->tif_rawcc;
	/* get each byte string */
	for (shft = 2*8; (shft -= 8) >= 0; ) {
		for (i = 0; i < npixels && cc > 0; ) {
			if (*bp >= 128) {		/* run */
				if( cc < 2 )
					break;
				rc = *bp++ + (2-128);
				b = (int16)(*bp++ << shft);
				cc -= 2;
				while (rc-- && i < npixels)
					tp[i++] |= b;
			} else {			/* non-run */
				rc = *bp++;		/* nul is noop */
				while (--cc && rc-- && i < npixels)
					tp[i++] |= (int16)*bp++ << shft;
			}
		}
		if (i != npixels) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
			TIFFErrorExt(tif->tif_clientdata, module,
			    "Not enough data at row %lu (short %I64d pixels)",
				     (unsigned long) tif->tif_row,
				     (unsigned __int64) (npixels - i));
#else
			TIFFErrorExt(tif->tif_clientdata, module,
			    "Not enough data at row %lu (short %llu pixels)",
				     (unsigned long) tif->tif_row,
				     (unsigned long long) (npixels - i));
#endif
			tif->tif_rawcp = (uint8*) bp;
			tif->tif_rawcc = cc;
			return (0);
		}
	}
	(*sp->tfunc)(sp, op, npixels);
	tif->tif_rawcp = (uint8*) bp;
	tif->tif_rawcc = cc;
	return (1);
}

static int
ZIPDecode(TIFF* tif, uint8* op, tmsize_t occ, uint16 s)
{
	static const char module[] = "ZIPDecode";
	ZIPState* sp = DecoderState(tif);

	(void) s;
	assert(sp != NULL);
	assert(sp->state == ZSTATE_INIT_DECODE);

        sp->stream.next_in = tif->tif_rawcp;
	sp->stream.avail_in = (uInt) tif->tif_rawcc;
        
	sp->stream.next_out = op;
	assert(sizeof(sp->stream.avail_out)==4);  /* if this assert gets raised,
	    we need to simplify this code to reflect a ZLib that is likely updated
	    to deal with 8byte memory sizes, though this code will respond
	    apropriately even before we simplify it */
	sp->stream.avail_out = (uInt) occ;
	if ((tmsize_t)sp->stream.avail_out != occ)
	{
		TIFFErrorExt(tif->tif_clientdata, module, "ZLib cannot deal with buffers this size");
		return (0);
	}
#if defined(__INTEL_COMPILER) && 1 /* VDM auto patch */
#   pragma ivdep
#   pragma swp
#   pragma unroll
#   pragma prefetch
#   if 0
#       pragma simd noassert
#   endif
#endif /* VDM auto patch */
	do {
		int state = inflate(&sp->stream, Z_PARTIAL_FLUSH);
		if (state == Z_STREAM_END)
			break;
		if (state == Z_DATA_ERROR) {
			TIFFErrorExt(tif->tif_clientdata, module,
			    "Decoding error at scanline %lu, %s",
			    (unsigned long) tif->tif_row, sp->stream.msg);
			if (inflateSync(&sp->stream) != Z_OK)
				return (0);
			continue;
		}
		if (state != Z_OK) {
			TIFFErrorExt(tif->tif_clientdata, module, "ZLib error: %s",
			    sp->stream.msg);
			return (0);
		}
	} while (sp->stream.avail_out > 0);
	if (sp->stream.avail_out != 0) {
		TIFFErrorExt(tif->tif_clientdata, module,
		    "Not enough data at scanline %lu (short " TIFF_UINT64_FORMAT " bytes)",
		    (unsigned long) tif->tif_row, (TIFF_UINT64_T) sp->stream.avail_out);
		return (0);
	}

        tif->tif_rawcp = sp->stream.next_in;
        tif->tif_rawcc = sp->stream.avail_in;

	return (1);
}