When trying to load TIFF images with pixRead it always fails about leptonica HOT 12 CLOSED

Can you share also tiff file?

from leptonica.

You can use any of these tiff files, they all have the same problem --> https://github.com/Sicos1977/TesseractOCR/tree/master/TesseractOCR.Tests/Data/Conversion

from leptonica.

C code works for me without a problem:

#include <leptonica/allheaders.h>

int main(int argc, char **argv) {
  char *filein;
  PIX *pixs;
  l_ok ret;
  l_int32  LeptMsgSeverity = 1;

  if (argc != 2)
     return fprintf(stderr," Syntax:  %s filein", argv[0]);

  filein = argv[1];

  if ((pixs = pixRead(filein)) == NULL) {
    ERROR_INT("pix not made", __func__, 1);
  } else {
    fprintf(stderr, "Leptonica loaded: %s\n", filein);
  }
 
  ret = pixWrite("pixs.png", pixs, IFF_PNG);
  if (ret > 0)
    ERROR_INT("ret of pixWrite: ", __func__, ret);
  pixDestroy(&pixs);
  return ret;
}

compiled with (MSVC 2019, Windows 10 64bit; libtiff 4.4.0):

cl test_tiff.c -I..\include ..\lib\leptonica-1.83.0.lib

e.g. test_tiff.exe photo_palette_4bpp.tif creates the correct png output...
Seems like a problem with wrapping leptonica in C# .NET...

from leptonica.

Weird because 1.82 works without any problems. Is there a way to see if the tif library is compiled into the output file?

from leptonica.

Well, you should see an error message (in the console/terminal) if you try to open unsupported image format.
Also, check the output of leptonica function getImagelibVersions.

You can also try to open an image with a format that does not need external lib (pbn, ppn, bmp) and save it as tiff...

from leptonica.

Images are saved in tiff format correctly.
Versions of built-in libraries in leptonica-1.83.0:

• libgif 5.2.1
• libjpeg 6b (libjpeg-turbo 2.0.6)
• libpng 1.6.37
• libtiff 4.3.0
• zlib 1.2.11

I think this is due to the fact that the image format (e. g. photo_rgb_32bpp.tif file) is not tiff but bitmap:

Looking at the commit d4ab740f6c0d40fe12ddc15c9ceba1f614711665 Leptonica does not support 32 bpp images.

from leptonica.

I checked one of the files with a hex editor and that seems like a tiff to me... as far as I know the first few bytes of a tiff image are always II

from leptonica.

Yes, this is true for all files except what I wrote above (photo_rgb_32bpp.tif)

from leptonica.

When I run >test_tiff.exe photo_rgb_32bpp.tif I see this message:

Error in pixReadMemBmp: 32 bpp rgba input data is not supported
Error in pixReadStream: bmp: no pix returned
Error in pixRead: pix not read
Error in main: pix not made
Error in pixWrite: pix not defined

from leptonica.

The only thing I find weird is that all files seem to work when using version 1.82. I have to dive deeper into this to see if I did something wrong but that will be next week because I'm busy with another project at the moment.

from leptonica.

1. As already mentioned by vsolominov photo_rgb_32bpp.tif is BMP file with wrong extensions. The same message you can get with IrfanView
2. leptonica 1.82 reads it - but when you run my tests code, the output in PNG does not have correct colors
3. leptonica 1.83 refuse to load it - reason is explain in this commit d4ab740

from leptonica.

1. As already mentioned by vsolominov photo_rgb_32bpp.tif is BMP file with wrong extensions. The same message you can get with IrfanView
2. leptonica 1.82 reads it - but when you run my tests code, the output in PNG does not have correct colors
3. leptonica 1.83 refuse to load it - reason is explain in this commit d4ab740

Okay, thinks missed that one.

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