Help with bad JPEG images converted from TIF

[Exilas]

Hi all,
I'm at a loss investigating an issue we had with JPEG images obtained from TIFF originals. This is a sample JPEG showing the issue.



Of course, the man has colors in the original TIFF, which is very large (about 550MB); however, size doesn't seem to be a factor, since other large TIFFs get converted correctly. The shaded gray background is correct, only the "overimposed" man is wrong.

I tried to compare a good and a bad TIFF using some analyzing tools, but I saw no evident difference that could explain this behaviour.

To complicate the issue further, I'm using a third-part SW that embeds some unknown version of IM for image processing; I can only modify the XML profile that's fed to IM, which is the following:

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<?xml version="1.0" encoding="UTF-8"?>
<IMW_MP_PROPERTIES>
 <OutputFormat>JPEG</OutputFormat>
 <Pages>0</Pages>
 <PROP name="Width" type="unsigned long" token="doc_token_width_tn">100</PROP>
 <PROP name="Height" type="unsigned long" token="doc_token_height_tn">100</PROP>
 <PROP name="enlarge" type="string" token="doc_token_enlarge">false</PROP>
 <Options>-limit memory doc_token_limit_memory -limit map doc_token_limit_map -limit area doc_token_limit_area -flatten -quality 80 -strip -filter Lanczos -profile "doc_token_cmyk_profile" -profile "doc_token_rgb_profile" -profile "doc_token_colorProfile" -colorspace doc_token_colorSpace</Options>
</IMW_MP_PROPERTIES>

Could you please hint about some possible cause or suggest a line of investigation?

Thanks

[snibgo]

I suspect it is a clipping path, often used to block-out backgrounds. See http://www.imagemagick.org/script/comma ... s.php#clip and following options.

Failing that, it's a bit large to put the tiff file somewhere like dropbox.com and paste the URL here, so:

Code: Select all

identify -verbose X.tiff

and paste the output here, between [ code ] and [ /code ].

[Exilas]

Snibgo,
thanks for your reply.

I see no clip option in the profile XML, so I guess the reason may be different.

Please find below the identify -verbose ouptut for both a good and a bad TIFF. I can't spot any real difference in the two files, but I'm a novice at this.

Any further help is really appreciated.

Thanks


BAD

Code: Select all

Image: d:\Downloads\11_077.tif
  Format: TIFF (Tagged Image File Format)
  Mime type: image/tiff
  Class: DirectClass
  Geometry: 7320x5484+0+0
  Resolution: 300x300
  Print size: 24.4x18.28
  Units: PixelsPerInch
  Type: ColorSeparationAlpha
  Base type: ColorSeparation
  Endianess: MSB
  Colorspace: CMYK
  Depth: 8-bit
  Channel depth:
    cyan: 8-bit
    magenta: 8-bit
    yellow: 8-bit
    black: 8-bit
    alpha: 8-bit
  Channel statistics:
    Cyan:
      min: 0 (0)
      max: 255 (1)
      mean: 137.161 (0.537885)
      standard deviation: 49.3868 (0.193674)
      kurtosis: 0.265992
      skewness: -0.137577
    Magenta:
      min: 0 (0)
      max: 255 (1)
      mean: 115.633 (0.453463)
      standard deviation: 51.4055 (0.20159)
      kurtosis: 0.211594
      skewness: 0.39526
    Yellow:
      min: 0 (0)
      max: 243 (0.952941)
      mean: 95.3686 (0.373994)
      standard deviation: 35.662 (0.139851)
      kurtosis: -0.0948723
      skewness: 0.0534431
    Black:
      min: 0 (0)
      max: 239 (0.937255)
      mean: 83.3326 (0.326794)
      standard deviation: 52.4248 (0.205587)
      kurtosis: 0.229723
      skewness: 0.571227
    Alpha:
      min: 0 (0)
      max: 255 (1)
      mean: 182.814 (0.716917)
      standard deviation: 114.658 (0.44964)
      kurtosis: -1.06912
      skewness: 0.963103
  Image statistics:
    Overall:
      min: 0 (0)
      max: 255 (1)
      mean: 100.736 (0.395044)
      standard deviation: 66.7056 (0.261591)
      kurtosis: 0.322236
      skewness: 0.465718
  Total ink density: 354.51%
  Alpha: cmyka(232,226,151,211,0)   #E8E297D300
  Rendering intent: Perceptual
  Gamma: 0.454545
  Chromaticity:
    red primary: (0.64,0.33)
    green primary: (0.3,0.6)
    blue primary: (0.15,0.06)
    white point: (0.3127,0.329)
  Background color: cmyka(255,255,255,0,1)
  Border color: cmyka(223,223,223,0,1)
  Matte color: cmyka(189,189,189,0,1)
  Transparent color: cmyka(0,0,0,0,0)
  Interlace: None
  Intensity: Undefined
  Compose: Over
  Page geometry: 7320x5484+0+0
  Dispose: Undefined
  Iterations: 0
  Compression: None
  Orientation: TopLeft
  Properties:
    date:create: 2014-03-04T18:16:09+01:00
    date:modify: 2014-03-04T18:16:18+01:00
    exif:ApertureValue: 8
    exif:DateTimeDigitized: 2013:06:14 19:45:43
    exif:DateTimeOriginal: 2013:06:14 19:45:43
    exif:ExposureTime: 0.00200001
    exif:FNumber: 16
    exif:FocalLength: 80
    exif:ISOSpeedRatings: 50
    exif:LightSource: 255
    exif:PixelXDimension: 7320
    exif:PixelYDimension: 5484
    exif:ShutterSpeedValue: 8.96578
    icc:copyright: PrintOpen 5.2.0 - (c) Copyright 2000-2006 Heidelberger Druckmaschinen AG. All Rights Reserved.
    icc:description: ISO Coated v2 (ECI)
    icc:manufacturer: ISO Coated v2 (ECI)
    icc:model: ISO Coated v2 (ECI)
    rdf:Bag: 
     
     
     
     
    
    signature: 2f9bca4b81ed252dcdf11b9771feb86dc5df0b0c765946e72135922b8527a2b7
    tiff:alpha: unassociated
    tiff:endian: msb
    tiff:make: Phase One
    tiff:model: IQ140
    tiff:photometric: separated
    tiff:rows-per-strip: 1
    tiff:software: Adobe Photoshop CS5 Macintosh
    tiff:timestamp: 2013:07:16 15:54:30
  Profiles:
    Profile-8bim: 25746 bytes
    Profile-icc: 1829077 bytes
    Profile-tiff:37724: 322482064 bytes
    Profile-xmp: 17526 bytes
  Artifacts:
    filename: d:\Downloads\11_077.tif
    verbose: true
  Tainted: False
  Filesize: 525.1MB
  Number pixels: 40.14M
  Pixels per second: 1.115MB
  User time: 3.156u
  Elapsed time: 0:37.014
  Version: ImageMagick 6.8.8-7 Q16 x86 2014-02-13 http://www.imagemagick.org

GOOD

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Image: d:\Downloads\18_091.tif
  Format: TIFF (Tagged Image File Format)
  Mime type: image/tiff
  Class: DirectClass
  Geometry: 5134x7081+0+0
  Resolution: 300x300
  Print size: 17.1133x23.6033
  Units: PixelsPerInch
  Type: ColorSeparationAlpha
  Base type: ColorSeparation
  Endianess: MSB
  Colorspace: CMYK
  Depth: 8-bit
  Channel depth:
    cyan: 8-bit
    magenta: 8-bit
    yellow: 8-bit
    black: 8-bit
    alpha: 8-bit
  Channel statistics:
    Cyan:
      min: 0 (0)
      max: 253 (0.992157)
      mean: 125.009 (0.49023)
      standard deviation: 47.7624 (0.187304)
      kurtosis: 1.24037
      skewness: -0.35695
    Magenta:
      min: 0 (0)
      max: 255 (1)
      mean: 126.405 (0.495707)
      standard deviation: 52.4278 (0.205599)
      kurtosis: 0.619188
      skewness: 1.36218
    Yellow:
      min: 0 (0)
      max: 232 (0.909804)
      mean: 101.957 (0.39983)
      standard deviation: 20.5659 (0.0806505)
      kurtosis: 1.60634
      skewness: 1.01318
    Black:
      min: 0 (0)
      max: 232 (0.909804)
      mean: 82.2312 (0.322475)
      standard deviation: 43.8796 (0.172077)
      kurtosis: 1.53956
      skewness: 1.28264
    Alpha:
      min: 0 (0)
      max: 255 (1)
      mean: 74.6512 (0.29275)
      standard deviation: 115.778 (0.45403)
      kurtosis: -1.16644
      skewness: -0.910974
  Image statistics:
    Overall:
      min: 0 (0)
      max: 255 (1)
      mean: 123.19 (0.483098)
      standard deviation: 64.4714 (0.252829)
      kurtosis: 1.10045
      skewness: 0.778629
  Total ink density: 334.902%
  Alpha: cmyka(124,98,95,65,0)   #7C625F4100
  Rendering intent: Perceptual
  Gamma: 0.454545
  Chromaticity:
    red primary: (0.64,0.33)
    green primary: (0.3,0.6)
    blue primary: (0.15,0.06)
    white point: (0.3127,0.329)
  Background color: cmyka(255,255,255,0,1)
  Border color: cmyka(223,223,223,0,1)
  Matte color: cmyka(189,189,189,0,1)
  Transparent color: cmyka(0,0,0,0,0)
  Interlace: None
  Intensity: Undefined
  Compose: Over
  Page geometry: 5134x7081+0+0
  Dispose: Undefined
  Iterations: 0
  Compression: None
  Orientation: TopLeft
  Properties:
    date:create: 2014-03-05T14:57:19+01:00
    date:modify: 2014-03-05T14:57:19+01:00
    exif:ApertureValue: 8
    exif:DateTimeDigitized: 2013:06:14 19:09:57
    exif:DateTimeOriginal: 2013:06:14 19:09:57
    exif:ExposureTime: 0.00200001
    exif:FNumber: 16
    exif:FocalLength: 80
    exif:ISOSpeedRatings: 50
    exif:LightSource: 255
    exif:PixelXDimension: 5134
    exif:PixelYDimension: 7081
    exif:ShutterSpeedValue: 8.96578
    icc:copyright: PrintOpen 5.2.0 - (c) Copyright 2000-2006 Heidelberger Druckmaschinen AG. All Rights Reserved.
    icc:description: ISO Coated v2 (ECI)
    icc:manufacturer: ISO Coated v2 (ECI)
    icc:model: ISO Coated v2 (ECI)
    rdf:Bag: 
     
     
     
     
    
    signature: f1a24d9ccbb2496d4d86c0db636c1c15f5353c90ce7e0b8101e67f57fc7e041e
    tiff:alpha: unassociated
    tiff:endian: lsb
    tiff:make: Phase One
    tiff:model: IQ140
    tiff:photometric: separated
    tiff:rows-per-strip: 1
    tiff:software: Adobe Photoshop CS5 Macintosh
    tiff:timestamp: 2013:07:26 14:22:58
  Profiles:
    Profile-8bim: 5614 bytes
    Profile-icc: 1829077 bytes
    Profile-tiff:37724: 283547716 bytes
    Profile-xmp: 19766 bytes
  Artifacts:
    filename: d:\Downloads\18_091.tif
    verbose: true
  Tainted: False
  Filesize: 467.2MB
  Number pixels: 36.35M
  Pixels per second: 2.104MB
  User time: 2.672u
  Elapsed time: 0:18.281
  Version: ImageMagick 6.8.8-7 Q16 x86 2014-02-13 http://www.imagemagick.org

[snibgo]

You have unassociated alpha. Try "-alpha off".

[Exilas]

Unfortunately -alpha off didn't any good.

To a profane (me) eye, it'd seem like the image has two layers, and for some reason one is "cropped off" during the jpeg creation. However, I see the -flatten option set, so I guess that option should address such kind of layers issue.

Any other help is greatly appreciated.

[snibgo]

Multiple layers are possible; Photoshop can "hide" layers that IM can't see. The bad file has "Profile-tiff:37724: 322482064 bytes", which is an awful lot of bytes, half the file.

Have you tried, from the command line:

Code: Select all

convert bad.tiff -alpha off -strip x.png

You might also try:

Code: Select all

exiftool -s2 -all -b -X -fXMP:XMP bad.tiff>badtiff.txt

... and post the results here.

[Exilas]

I managed to track down the exact command that is issued by the system:

Code: Select all

convert.exe 11_077.tif -colorspace RGB -density 96 -limit memory 2048 -limit map 4096 -limit area 8192 -background white -flatten -quality 80 -strip -filter Lanczos  -profile "sRGB Color Space Profile.icm" -colorspace RGB -resize 300x300 11_077.jpg

I did a lot of trial-and-error unwitting attempts, and I discovered that by removing both the -flatten and -resize 300x300 options the output jpeg looks fine.

Does that make any sense to you? Do you see a way to resize the image without mangling it? Is the double -colorspace RGB option really needed? Is the sRGB profile coherent with the RGB colorspace? What difference in the original TIFFs makes that command good for one and bad for the other?

I feel utterly out of my depth...

Thanks a lot!

[snibgo]

What version of IM? ("convert -version".)

For recent versions of IM, "-colorspace RGB" would be bad news, and give incorrect results. For old versions, it may be needed. In the bad old days, IM had sRGB and RGB the wrong way round. I forget when that was corrected.

"-strip" is bad, and you should remove it. Both files contain CMYK colour profiles, and the correct way to convert them to sRGB is with another "-profile", which converts pixels from the old profile to the new one. But "-strip" removes the old profile, it just wipes it out, so IM can't then convert the pixels from the old profile to the new one. (As the command stands, "-profile" does nothing, and the conversion from CMYK to RGB is done by one of the "-colorspace" operations.)

"-background white -flatten" puts white behind the image and removes transparency, making each pixel the appropriate mix of its previous colour and white. If you don't "-flatten", then converting to jpeg should simply remove transparency, without changing the colour. Using "-alpha off" should also do this. But putting "-alpha off" after "-flatten" will do nothing, as by then there is no alpha to turn off.

"-resize 300x300" should make no difference to transparency, or anything else really. Apart from the size, of course.

See http://www.imagemagick.org/script/comma ... ptions.php for the detail of each operation.

[Exilas]

Snibgo,
once again thanks for your help. In the end, I managed to solve the issue; due to some limitation I have in changing the parameters fed to IM (some are sort of "builtin"), this is the issued command now:

Code: Select all

convert.exe 11_077.tif -colorspace RGB -density 96 -limit memory 2048 -limit map 4096 -limit area 8192 -background white -alpha off -quality 80 -strip -filter Lanczos  -profile "sRGB Color Space Profile.icm" -colorspace RGB -resize 300x300 11_077.jpg

that is, I replaced -flatten with -alpha off, and this seems to do the trick.

It still escapes me which is really the difference between the good and bad original TIFFs, but I guess I can live nonetheless

Really, I wouldn't have come out of this mess without your kind help. Thanks and kudos.

Regards