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TIFF and LibTiff Mail List Archive

Thread

2005.05.27 07:46 "[Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & compress", by Kelvin Zhong
2005.05.28 17:21 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & compress", by Joris Van Damme
2005.05.30 09:58 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & co mpress", by Kelvin Zhong
2005.05.30 13:32 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & compress", by Jean-Yves Le Ridant
2005.05.31 07:24 "Re: [Tiff] how to convert a JPEG-IN-TIFF file to jpeg file without decomress & com press", by Kelvin Zhong
2005.06.29 20:21 "[Tiff] copying jpeg tables", by James Carroll

2005.06.29 20:21 "[Tiff] copying jpeg tables", by James Carroll

Hi, I'm trying to do an ultra-fast copy of JPEG compressed TIFF tiles from one file to another...

tiffcp cheats and decodes each tile, then re-encodes it. I'm hoping to minimize the processor time of decoding and re-encoding.

I'm copying all the standard tags, and using ReadRawTile and WriteRawTile to transfer the tiles, but I also have to copy some other stuff... I'm guessing at least the JpegTables

How do I copy the JPEG_TABLES?

Portions of my code below... and tiffdump that shows the tables below that.

Thanks,

-Jim

..... (lots of tags copied)

if (TIFFGetField(tifIn, TIFFTAG_TILEWIDTH, &tileWidth))

{

TIFFSetField(tifOut, TIFFTAG_TILEWIDTH, tileWidth);

}

if (TIFFGetField(tifIn, TIFFTAG_TILELENGTH, &tileLength))

{

TIFFSetField(tifOut, TIFFTAG_TILELENGTH, tileLength);

}

// Copy JPEG Tables

???????????????????????????????????????????????

// For each tile, read raw, and write raw

tdata_t buf;

ttile_t tile;

buf = _TIFFmalloc(TIFFTileSize(tifIn));

for (tile = 0; tile < TIFFNumberOfTiles(tifIn); tile++)

{

                        tsize_t tileSize = TIFFReadRawTile(tifIn, tile,
buf, (tsize_t) -1);

TIFFWriteRawTile(tifOut, tile, buf, tileSize);

}

_TIFFfree(buf);

TIFFClose(tifIn);

TIFFClose(tifOut);

tiffdump for the image I'm trying to copy:

vs00523_p4.tif:

Magic: 0x4949 <little-endian> Version: 0x2a

Directory 0: offset 499632 (0x79fb0) next 0 (0)

ImageWidth (256) SHORT (3) 1<1950>

ImageLength (257) SHORT (3) 1<2188>

BitsPerSample (258) SHORT (3) 3<8 8 8>

Compression (259) SHORT (3) 1<7>

Photometric (262) SHORT (3) 1<6>

Orientation (274) SHORT (3) 1<1>

SamplesPerPixel (277) SHORT (3) 1<3>

PlanarConfig (284) SHORT (3) 1<1>

TileWidth (322) SHORT (3) 1<256>

TileLength (323) SHORT (3) 1<256>

TileOffsets (324) LONG (4) 72 <8 1188 7813 20723 38271 53379 59816 60993 62116 70 308 88528 99915 103191 107125 123874 137313 139069 154530 166768 167906 168969 1 70032 173615 192932 ...>

TileByteCounts (325) LONG (4) 72 <1180 6625 12910 17548 15108 6437 1177 1123 8192 18220 11387 3276 3934 16749 13439 1756 15461 12238 1138 1063 1063 3583 19317 81 35 ...>

347 (0x15b) UNDEFINED (7) 574 <0xff 0xd8 0xff 0xdb 00 0x43 00 0x6 0x4 0x5 0x6 0x5 0x4 0x6 0x6 0x5 0x6 0x7 0x7 0x6 0x8 0xa 0x10 0xa ...>

YCbCrSubsampling (530) SHORT (3) 2<2 2>

ReferenceBlackWhite (532) RATIONAL (5) 6<0 255 128 255 128 255>

the 347 is the tag that shows there are 574 elements in the jpeg tables