C++ EncoderState函數代碼示例

/*
 * Reset encoding state at the start of a strip.
 */
static int
LZMAPreEncode(TIFF* tif, uint16 s)
{
	static const char module[] = "LZMAPreEncode";
	LZMAState *sp = EncoderState(tif);

	(void) s;
	assert(sp != NULL);
	if( sp->state != LSTATE_INIT_ENCODE )
            tif->tif_setupencode(tif);

	sp->stream.next_out = tif->tif_rawdata;
	sp->stream.avail_out = (size_t)tif->tif_rawdatasize;
	if ((tmsize_t)sp->stream.avail_out != tif->tif_rawdatasize) {
		TIFFErrorExt(tif->tif_clientdata, module,
			     "Liblzma cannot deal with buffers this size");
		return 0;
	}
	return (lzma_stream_encoder(&sp->stream, sp->filters, sp->check) == LZMA_OK);
}

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

	assert(sp != NULL);
	if (sp->state & ZSTATE_INIT_DECODE) {
		inflateEnd(&sp->stream);
		sp->state = 0;
	}

	if (deflateInit(&sp->stream, sp->zipquality) != Z_OK) {
		TIFFErrorExt(tif->tif_clientdata, module, "%s", sp->stream.msg);
		return (0);
	} else {
		sp->state |= ZSTATE_INIT_ENCODE;
		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 (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
ZIPSetupEncode(TIFF* tif)
{
	ZIPState* sp = EncoderState(tif);
	static char module[] = "ZIPSetupEncode";

	assert(sp != NULL);
	/*
	 * We use the undocumented feature of a negiatve window
	 * bits to suppress writing the header in the output
	 * stream.  This is necessary when the resulting image
	 * is made up of multiple strips or tiles as otherwise
	 * libgz will not write a header for each strip/tile and
	 * the decoder will fail.
	 */
	if (deflateInit2(&sp->stream, Z_DEFAULT_COMPRESSION,
	    DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, 0) != Z_OK) {
		TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
		return (0);
	} else
		return (1);
}

/*
 * Finish off an encoded strip by flushing the last
 * string and tacking on an End Of Information code.
 */
static int
ZIPPostEncode(TIFF* tif)
{
	static const char module[] = "ZIPPostEncode";
	ZIPState *sp = EncoderState(tif);
	int state;

	sp->stream.avail_in = 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 {
		state = deflate(&sp->stream, Z_FINISH);
		switch (state) {
		case Z_STREAM_END:
		case Z_OK:
			if ((tmsize_t)sp->stream.avail_out != tif->tif_rawdatasize)
			{
				tif->tif_rawcc =  tif->tif_rawdatasize - sp->stream.avail_out;
				TIFFFlushData1(tif);
				sp->stream.next_out = tif->tif_rawdata;
				sp->stream.avail_out = (uInt) tif->tif_rawdatasize;  /* this is a safe typecast, as check is made already in ZIPPreEncode */
			}
			break;
		default:
			TIFFErrorExt(tif->tif_clientdata, module, "ZLib error: %s",
			    sp->stream.msg);
			return (0);
		}
	} while (state != Z_STREAM_END);
	return (1);
}

/*
 * Encode a chunk of pixels.
 */
static int
ZIPEncode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s) {
    ZIPState* sp = EncoderState(tif);
    static const char module[] = "ZIPEncode";

    (void) s;
    sp->stream.next_in = bp;
    sp->stream.avail_in = cc;
    do {
        if (deflate(&sp->stream, Z_NO_FLUSH) != Z_OK) {
            TIFFError(module, "%s: Encoder error: %s",
                      tif->tif_name, sp->stream.msg);
            return (0);
        }
        if (sp->stream.avail_out == 0) {
            tif->tif_rawcc = tif->tif_rawdatasize;
            TIFFFlushData1(tif);
            sp->stream.next_out = tif->tif_rawdata;
            sp->stream.avail_out = tif->tif_rawdatasize;
        }
    } while (sp->stream.avail_in > 0);
    return (1);
}

/*
 * Encode a chunk of pixels.
 */
static int
ZIPEncode(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s)
{
	static const char module[] = "ZIPEncode";
	ZIPState *sp = EncoderState(tif);

	assert(sp != NULL);
	assert(sp->state == ZSTATE_INIT_ENCODE);

	(void) s;
	sp->stream.next_in = bp;
	assert(sizeof(sp->stream.avail_in)==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
	    appropriately even before we simplify it */
	sp->stream.avail_in = (uInt) cc;
	if ((tmsize_t)sp->stream.avail_in != cc)
	{
		TIFFErrorExt(tif->tif_clientdata, module, "ZLib cannot deal with buffers this size");
		return (0);
	}
	do {
		if (deflate(&sp->stream, Z_NO_FLUSH) != Z_OK) {
			TIFFErrorExt(tif->tif_clientdata, module, 
				     "Encoder error: %s",
				     SAFE_MSG(sp));
			return (0);
		}
		if (sp->stream.avail_out == 0) {
			tif->tif_rawcc = tif->tif_rawdatasize;
			TIFFFlushData1(tif);
			sp->stream.next_out = tif->tif_rawdata;
			sp->stream.avail_out = (uInt) tif->tif_rawdatasize;  /* this is a safe typecast, as check is made already in ZIPPreEncode */
		}
	} while (sp->stream.avail_in > 0);
	return (1);
}

/*
* Encode a chunk of pixels.
*/
static int
LERCEncode(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s)
{
        static const char module[] = "LERCEncode";
        LERCState *sp = EncoderState(tif);

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

        if( (uint64)sp->uncompressed_offset +
                                    (uint64)cc > sp->uncompressed_size )
        {
            TIFFErrorExt(tif->tif_clientdata, module,
                         "Too many bytes written");
            return 0;
        }

        memcpy(sp->uncompressed_buffer + sp->uncompressed_offset,
               bp, cc);
        sp->uncompressed_offset += (unsigned)cc;

        return 1;
}

/*
 * Reset encoding state at the start of a strip.
 */
static int
ZIPPreEncode(TIFF* tif, uint16 s)
{
	static const char module[] = "ZIPPreEncode";
	ZIPState *sp = EncoderState(tif);

	(void) s;
	assert(sp != NULL);
	if( sp->state != ZSTATE_INIT_ENCODE )
            tif->tif_setupencode( tif );

	sp->stream.next_out = tif->tif_rawdata;
	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
	    appropriately even before we simplify it */
	sp->stream.avail_out = (uInt)tif->tif_rawdatasize;
	if ((tmsize_t)sp->stream.avail_out != tif->tif_rawdatasize)
	{
		TIFFErrorExt(tif->tif_clientdata, module, "ZLib cannot deal with buffers this size");
		return (0);
	}
	return (deflateReset(&sp->stream) == Z_OK);
}

/*
* Finish off an encoded strip by flushing it.
*/
static int
TWebPPostEncode(TIFF* tif)
{
  static const char module[] = "WebPPostEncode";
  int64_t stride;
  WebPState *sp = EncoderState(tif);
  assert(sp != NULL);

  assert(sp->state == LSTATE_INIT_ENCODE);

  stride = (int64_t)sp->sPicture.width * sp->nSamples;

#if WEBP_ENCODER_ABI_VERSION >= 0x0100
  if (sp->nSamples == 4) {
      if (!WebPPictureImportRGBA(&sp->sPicture, sp->pBuffer, (int)stride)) {
          TIFFErrorExt(tif->tif_clientdata, module,
                    "WebPPictureImportRGBA() failed" );
          return 0;
      }
  }
  else
#endif
  if (!WebPPictureImportRGB(&sp->sPicture, sp->pBuffer, (int)stride)) {
      TIFFErrorExt(tif->tif_clientdata, module,
                    "WebPPictureImportRGB() failed");
      return 0;
  }
  
  if (!WebPEncode(&sp->sEncoderConfig, &sp->sPicture)) {

#if WEBP_ENCODER_ABI_VERSION >= 0x0100
    const char* pszErrorMsg = NULL;
    switch(sp->sPicture.error_code) {
    case VP8_ENC_ERROR_OUT_OF_MEMORY:
        pszErrorMsg = "Out of memory"; break;
    case VP8_ENC_ERROR_BITSTREAM_OUT_OF_MEMORY:
        pszErrorMsg = "Out of memory while flushing bits"; break;
    case VP8_ENC_ERROR_NULL_PARAMETER:
        pszErrorMsg = "A pointer parameter is NULL"; break;
    case VP8_ENC_ERROR_INVALID_CONFIGURATION:
        pszErrorMsg = "Configuration is invalid"; break;
    case VP8_ENC_ERROR_BAD_DIMENSION:
        pszErrorMsg = "Picture has invalid width/height"; break;
    case VP8_ENC_ERROR_PARTITION0_OVERFLOW:
        pszErrorMsg = "Partition is bigger than 512k. Try using less "
            "SEGMENTS, or increase PARTITION_LIMIT value";
        break;
    case VP8_ENC_ERROR_PARTITION_OVERFLOW:
        pszErrorMsg = "Partition is bigger than 16M";
        break;
    case VP8_ENC_ERROR_BAD_WRITE:
        pszErrorMsg = "Error while fludshing bytes"; break;
    case VP8_ENC_ERROR_FILE_TOO_BIG:
        pszErrorMsg = "File is bigger than 4G"; break;
    case VP8_ENC_ERROR_USER_ABORT:
        pszErrorMsg = "User interrupted";
        break;
    default:
        TIFFErrorExt(tif->tif_clientdata, module,
                "WebPEncode returned an unknown error code: %d",
                sp->sPicture.error_code);
        pszErrorMsg = "Unknown WebP error type.";
        break;
    }
    TIFFErrorExt(tif->tif_clientdata, module,
             "WebPEncode() failed : %s", pszErrorMsg);
#else
    TIFFErrorExt(tif->tif_clientdata, module,
             "Error in WebPEncode()");
#endif
    return 0;
  }

  sp->sPicture.custom_ptr = NULL;

  if (!TIFFFlushData1(tif))
  {
    TIFFErrorExt(tif->tif_clientdata, module,
      "Error flushing TIFF WebP encoder.");
    return 0;
  }

  return 1;
}

static int
TWebPSetupEncode(TIFF* tif)
{
  static const char module[] = "WebPSetupEncode";
  uint16 nBitsPerSample = tif->tif_dir.td_bitspersample;
  uint16 sampleFormat = tif->tif_dir.td_sampleformat;
  
  WebPState* sp = EncoderState(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 (sp->state & LSTATE_INIT_DECODE) {
    WebPIDelete(sp->psDecoder);
    WebPFreeDecBuffer(&sp->sDecBuffer);
    sp->psDecoder = NULL;
    sp->last_y = 0;
    sp->state = 0;
  }

  sp->state |= LSTATE_INIT_ENCODE;

  if (!WebPPictureInit(&sp->sPicture)) {
    TIFFErrorExt(tif->tif_clientdata, module,
        "Error initializing WebP picture.");
    return 0;
  }

  if (!WebPConfigInitInternal(&sp->sEncoderConfig, WEBP_PRESET_DEFAULT,
                              sp->quality_level,
                              WEBP_ENCODER_ABI_VERSION)) {
    TIFFErrorExt(tif->tif_clientdata, module,
      "Error creating WebP encoder configuration.");
    return 0;
  }

  // WebPConfigInitInternal above sets lossless to false
  #if WEBP_ENCODER_ABI_VERSION >= 0x0100
    sp->sEncoderConfig.lossless = sp->lossless;
    if (sp->lossless) {
      sp->sPicture.use_argb = 1;
    }
  #endif

  if (!WebPValidateConfig(&sp->sEncoderConfig)) {
    TIFFErrorExt(tif->tif_clientdata, module,
      "Error with WebP encoder configuration.");
    return 0;
  }

  return 1;
}

/*
 * Encode a chunk of pixels.
 *
 * Uses an open addressing double hashing (no chaining) on the 
 * prefix code/next character combination.  We do a variant of
 * Knuth's algorithm D (vol. 3, sec. 6.4) along with G. Knott's
 * relatively-prime secondary probe.  Here, the modular division
 * first probe is gives way to a faster exclusive-or manipulation. 
 * Also do block compression with an adaptive reset, whereby the
 * code table is cleared when the compression ratio decreases,
 * but after the table fills.  The variable-length output codes
 * are re-sized at this point, and a CODE_CLEAR is generated
 * for the decoder. 
 */
static int
LZWEncode(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s)
{
	register LZWCodecState *sp = EncoderState(tif);
	register long fcode;
	register hash_t *hp;
	register int h, c;
	hcode_t ent;
	long disp;
	long incount, outcount, checkpoint;
	unsigned long nextdata;
        long nextbits;
	int free_ent, maxcode, nbits;
	uint8* op;
	uint8* limit;

	(void) s;
	if (sp == NULL)
		return (0);

        assert(sp->enc_hashtab != NULL);

	/*
	 * Load local state.
	 */
	incount = sp->enc_incount;
	outcount = sp->enc_outcount;
	checkpoint = sp->enc_checkpoint;
	nextdata = sp->lzw_nextdata;
	nextbits = sp->lzw_nextbits;
	free_ent = sp->lzw_free_ent;
	maxcode = sp->lzw_maxcode;
	nbits = sp->lzw_nbits;
	op = tif->tif_rawcp;
	limit = sp->enc_rawlimit;
	ent = (hcode_t)sp->enc_oldcode;

	if (ent == (hcode_t) -1 && cc > 0) {
		/*
		 * NB: This is safe because it can only happen
		 *     at the start of a strip where we know there
		 *     is space in the data buffer.
		 */
		PutNextCode(op, CODE_CLEAR);
		ent = *bp++; cc--; incount++;
	}
	while (cc > 0) {
		c = *bp++; cc--; incount++;
		fcode = ((long)c << BITS_MAX) + ent;
		h = (c << HSHIFT) ^ ent;	/* xor hashing */
#ifdef _WINDOWS
		/*
		 * Check hash index for an overflow.
		 */
		if (h >= HSIZE)
			h -= HSIZE;
#endif
		hp = &sp->enc_hashtab[h];
		if (hp->hash == fcode) {
			ent = hp->code;
			continue;
		}
		if (hp->hash >= 0) {
			/*
			 * Primary hash failed, check secondary hash.
			 */
			disp = HSIZE - h;
			if (h == 0)
				disp = 1;
			do {
				/*
				 * Avoid pointer arithmetic because of
				 * wraparound problems with segments.
				 */
				if ((h -= disp) < 0)
					h += HSIZE;
				hp = &sp->enc_hashtab[h];
				if (hp->hash == fcode) {
					ent = hp->code;
					goto hit;
				}
			} while (hp->hash >= 0);
		}
		/*
		 * New entry, emit code and add to table.
		 */
//.........這裏部分代碼省略.........

/*
* Finish off an encoded strip by flushing it.
*/
static int
LERCPostEncode(TIFF* tif)
{
        lerc_status lerc_ret;
        static const char module[] = "LERCPostEncode";
        LERCState *sp = EncoderState(tif);
        unsigned int numBytes = 0;
        unsigned int numBytesWritten = 0;
        TIFFDirectory *td = &tif->tif_dir;
        int use_mask = 0;
        unsigned dst_nbands = td->td_samplesperpixel;

        if( sp->uncompressed_offset != sp->uncompressed_size )
        {
            TIFFErrorExt(tif->tif_clientdata, module,
                         "Unexpected number of bytes in the buffer");
            return 0;
        }

        /* Extract alpha mask (if containing only 0 and 255 values, */
        /* and compact array of regular bands */
        if( td->td_planarconfig == PLANARCONFIG_CONTIG &&
            td->td_extrasamples > 0 &&
            td->td_sampleinfo[td->td_extrasamples-1] == EXTRASAMPLE_UNASSALPHA &&
            GetLercDataType(tif) == 1 )
        {
            unsigned dst_stride = (td->td_samplesperpixel - 1) *
                                            (td->td_bitspersample / 8);
            unsigned src_stride = td->td_samplesperpixel *
                                            (td->td_bitspersample / 8);
            unsigned i = 0;
            unsigned nb_pixels = sp->segment_width * sp->segment_height;

            use_mask = 1;
            for( i = 0 ; i < nb_pixels; i++)
            {
                int v = sp->uncompressed_buffer[
                            i * src_stride + td->td_samplesperpixel - 1];
                if( v != 0 && v != 255 )
                {
                    use_mask = 0;
                    break;
                }
            }

            if( use_mask )
            {
                dst_nbands --;
                /* First pixels must use memmove due to overlapping areas */
                for( i = 0 ;i < dst_nbands && i < nb_pixels; i++)
                {
                    memmove( sp->uncompressed_buffer + i * dst_stride,
                            sp->uncompressed_buffer + i * src_stride,
                            dst_stride );
                    sp->mask_buffer[i] = sp->uncompressed_buffer[
                        i * src_stride + td->td_samplesperpixel - 1];
                }
                for(; i < nb_pixels; i++)
                {
                    memcpy( sp->uncompressed_buffer + i * dst_stride,
                            sp->uncompressed_buffer + i * src_stride,
                            dst_stride );
                    sp->mask_buffer[i] = sp->uncompressed_buffer[
                        i * src_stride + td->td_samplesperpixel - 1];
                }
            }
        }

#if 0
        lerc_ret = lerc_computeCompressedSize(
            sp->uncompressed_buffer,
            sp->lerc_version,
            GetLercDataType(tif),
            td->td_planarconfig == PLANARCONFIG_CONTIG ?
                dst_nbands : 1,
            sp->segment_width,
            sp->segment_height,
            1,
            use_mask ? sp->mask_buffer : NULL,
            sp->maxzerror,
            &numBytes);
        if( lerc_ret != 0 )
        {
            TIFFErrorExt(tif->tif_clientdata, module,
                         "lerc_computeCompressedSize() failed");
            return 0;
        }
#else
        numBytes = sp->uncompressed_alloc;
#endif

        if( sp->compressed_size < numBytes )
        {
            _TIFFfree(sp->compressed_buffer);
            sp->compressed_buffer = _TIFFmalloc(numBytes);
            if( !sp->compressed_buffer )
            {
//.........這裏部分代碼省略.........

/*
 * Encode a row of 16-bit pixels.
 */
static int
LogL16Encode(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s)
{
	LogLuvState* sp = EncoderState(tif);
	int shft;
	tmsize_t i;
	tmsize_t j;
	tmsize_t npixels;
	uint8* op;
	int16* tp;
	int16 b;
	tmsize_t occ;
	int rc=0, mask;
	tmsize_t beg;

	assert(s == 0);
	assert(sp != NULL);
	npixels = cc / sp->pixel_size;

	if (sp->user_datafmt == SGILOGDATAFMT_16BIT)
		tp = (int16*) bp;
	else {
		tp = (int16*) sp->tbuf;
		assert(sp->tbuflen >= npixels);
		(*sp->tfunc)(sp, bp, npixels);
	}
	/* compress each byte string */
	op = tif->tif_rawcp;
	occ = tif->tif_rawdatasize - tif->tif_rawcc;
	for (shft = 2*8; (shft -= 8) >= 0; )
		for (i = 0; i < npixels; i += rc) {
			if (occ < 4) {
				tif->tif_rawcp = op;
				tif->tif_rawcc = tif->tif_rawdatasize - occ;
				if (!TIFFFlushData1(tif))
					return (-1);
				op = tif->tif_rawcp;
				occ = tif->tif_rawdatasize - tif->tif_rawcc;
			}
			mask = 0xff << shft;		/* find next run */
			for (beg = i; beg < npixels; beg += rc) {
				b = (int16) (tp[beg] & mask);
				rc = 1;
				while (rc < 127+2 && beg+rc < npixels &&
				    (tp[beg+rc] & mask) == b)
					rc++;
				if (rc >= MINRUN)
					break;		/* long enough */
			}
			if (beg-i > 1 && beg-i < MINRUN) {
				b = (int16) (tp[i] & mask);/*check short run */
				j = i+1;
				while ((tp[j++] & mask) == b)
					if (j == beg) {
						*op++ = (uint8)(128-2+j-i);
						*op++ = (uint8)(b >> shft);
						occ -= 2;
						i = beg;
						break;
					}
			}