• Hello,


    I use conquest as a dicom print scp with a logic7 US and a Siemens Somatom CT and works fine. However with the Siemens CT I face the following problem.


    In the printouts (usually using 3x4 and 5x4 layout on A3 sized paper) the image texts are distorted (they are somehow pixelized and not smooth) and therefore not readable. It looks like when the dicom print image is transformed to BMP the interpolation is off so the image gets a little bit distorted when the size is adjusted to fit the default printer paper size.


    The configuration we use is the following:


    1. Xerox 7525 printer with 1200dpi and A3 as default settings
    2. The Siemens Somatom Duo CT scanner is configured to "see" the Conquest Dicom Print SCP as a Condonics Horizon printer (it was the only availble with paper as an option in CT Scanner configuration menu) and sends the print jobs using 8x10 film size in order to reduce image resolution to about 2300x2000 pixels image in order to be small enough to cope with Xerox's resolution. (if we set the film size to 11x14 the Dicom print image size resolution is about 5000x4300 so perhaps exceeds printer PPI)


    I did the following test succesfully to verify that the printer can deal with the image size. 1) I stopped the conquest user interface so all print jobs were qeued in the print_data folder 2. I opened a DICOM print file with a Dicom Viewer and copy paste the image (1to1 scale) in a Word file (A3 sized) 3. I printed the word file to the default printer and the image as well as the image text was of great quality. So that makes me guess that something goes wrong during the processing within the conquest user interface, propably the transformation of image from DICOM to BMP, such as absence of interpolation and smoothing.


    Thanking you in advance for your help.


    Dimitris Skordias

  • Hi,


    There are two steps: first images exceeding 1600 pixels horizontally are downsized in integral steps. This happens from server version 1.4.16. The command used is:


    dgate --convert_to_bmp:dicomfile,1600,bitmapfile


    Then the default printer resolution is used. This may be e.g., 300 dpi which might incur another downsize.


    Can you try the first step by manually performing the dgate -- command listed above on the printer files?


    Regards,


    Marcel

  • Hi Marcel and thanks for the reply !


    I did the test you mentioned...actually I used a Dicom print file with layout of 4x5 and resolution of 4320x5025 (this was the original film box produced by the Siemens CT) and convert it to bmp with the dgate command using 1600 size as an option. The result was a BMP file with resolution of 1080x1256 and 24bit depth and filesize of 3,88MB. The image quality was degradated (quite pixelized) because of the downsizing and of course the Image text was totally unreadable.


    When I increased the size in the dgate command to about 8-9K then the image quality was similar to that of the original dicom image.


    Any ideas how to improve the situation ? Is there a way to change the default 1600 size in conquest configuration ?


    By the way what are the w/l/f options of the dgate convert_to_bmp command ?


    Kind regards,


    Dimitris.

  • Hi Dimitris,


    to fix this I have to change the call to the dgate -- command hardcoded in the GUI. This means a new server release (I will make it configurable then).


    The w/l/f parameter means window/level/frame. The first parameters set contrast (auto if not set), the f parameter selects the frame out of a multiframe image (default 0).


    Marcel

  • Hi,


    A next full release (including GUI) would be in order, but especially updating all the documentation is a lot of work. The fix will definitively be included but it may take 1-2 months.


    Marcel

  • Hi,


    With a hex editor you can for now patch conquestdicomserver.exe: seek for ascii ',1600', and replace the ascii '1' with a '9' (it occurs 5 times). I just tried this and it works.


    Marcel

  • Marcel hi again...


    As i mentioned in my previous reply the problem with the text and the resolution was fixed thanks to your suggestion !


    However I would appreciate your help on another issue that arised on dicom print again with the Siemens Somatom CT. Actually the end users complain that the contrast and the brightness level of the printouts vary depending the exam type ie in brain exams they are acceptable while in other exams such as spine are not.


    Do you think that this is related with the conquest side (SCP) or it relies entirely on the (SCU) side ie the CT image processing and filming software (called syngo). If the CT operator would adjust the window/level of the images in the filmbox prior to sending them for printing would this improve the quality ?


    In the literature i noticed about presentation LUT...is this relevant in our case ?


    Regards,


    Dimitris.

  • Hi Dimitris,


    The print code uses the same auto-level window mechanism that is present in the dicom browser. I.e., at present level and window is not read from the printing source. This is a limitation that is not easily overcome. Can you have a look in the stored printer-files whether there is any level/window info there?


    Marcel

  • Hi Marcel,


    The default values in all stored dicom print files are L=128, W=256.


    Who sets these values SCP or SCU ? (I guess it is the SCP conquest as it is identical for all modalities ...I got a print request from a US and it is the same as with the CT ones)


    Thanks.

  • Hi Marcel,


    below you may find the dicom data of a print file.


    Thanks


    --------------------------------------


    Dicom-File-Format


    # Dicom-Meta-Information-Header
    # Used TransferSyntax: Little Endian Explicit
    (0002,0000) UL 102 # 4, 1 FileMetaInformationGroupLength
    (0002,0001) OB 00\01 # 2, 1 FileMetaInformationVersion
    (0002,0010) UI =LittleEndianImplicit # 18, 1 TransferSyntaxUID
    (0002,0012) UI [1.2.826.0.1.3680043.2.135.1066.101] # 34, 1 ImplementationClassUID
    (0002,0013) SH [1.4.16/WIN32] # 12, 1 ImplementationVersionName


    # Dicom-Data-Set
    # Used TransferSyntax: Little Endian Implicit
    (0008,0018) UI (no value available) # 0, 0 SOPInstanceUID
    (0008,0020) DA (no value available) # 0, 0 StudyDate
    (0008,0060) CS (no value available) # 0, 0 Modality
    (0008,1030) LO (no value available) # 0, 0 StudyDescription
    (0008,103e) LO (no value available) # 0, 0 SeriesDescription
    (0020,0011) IS (no value available) # 0, 0 SeriesNumber
    (0020,0013) IS (no value available) # 0, 0 InstanceNumber
    (0028,0000) UL 102 # 4, 1 GenericGroupLength
    (0028,0002) US 1 # 2, 1 SamplesPerPixel
    (0028,0004) CS [MONOCHROME2] # 12, 1 PhotometricInterpretation
    (0028,0010) US 5025 # 2, 1 Rows
    (0028,0011) US 4320 # 2, 1 Columns
    (0028,0034) IS [1\1] # 4, 2 PixelAspectRatio
    (0028,0100) US 8 # 2, 1 BitsAllocated
    (0028,0101) US 8 # 2, 1 BitsStored
    (0028,0102) US 7 # 2, 1 HighBit
    (0028,0103) US 0 # 2, 1 PixelRepresentation
    (7fe0,0000) UL 21708008 # 4, 1 ACR_NEMA_2C_VariablePixelDataGroupLength
    (7fe0,0010) OW (no value available) # 0, 1 PixelData


    <PropertySet>
    <Property id='ContentDate' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='ContentDateTime' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='ContentTime' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='DocumentColorSpace' upperBound='' lowerBound='' default='Grayscale' isModified='0'>Grayscale</Property>
    <Property id='DocumentHeight' upperBound='' lowerBound='' default='5025' isModified='0'>5025</Property>
    <Property id='DocumentNumber' upperBound='0' lowerBound='0' default='0' isModified='0'>0</Property>
    <Property id='DocumentTree' upperBound='' lowerBound='' default='patient_unique_id%2f....%2fdicom_study_id%2f1.3.6.1.4.1.24930.1346697517.26500.4%2fdicom_series_id%2f1.3.6.1.4.1.24930.1346697517.19169.5%2fdicom_sop_id%2f1.3.6.1.4.1.24930.1346697517.15724.6' isModified='1'>patient_unique_id%2f....%2fdicom_study_id%2f1.3.6.1.4.1.24930.1346697517.26500.4%2fdicom_series_id%2f1.3.6.1.4.1.24930.1346697517.19169.5%2fsequence_id%2f0%2fdicom_sop_id%2f1.3.6.1.4.1.24930.1346697517.15724.6</Property>
    <Property id='DocumentWidth' upperBound='' lowerBound='' default='4320' isModified='0'>4320</Property>
    <Property id='FileName' upperBound='' lowerBound='' default='1.2.826.0.1.3680043.2.135.734653.43121060.6.1346430.0.1.1.0.dcm' isModified='0'>1.2.826.0.1.3680043.2.135.734653.43121060.6.1346430.0.1.1.0.dcm</Property>
    <Property id='FilePath' upperBound='' lowerBound='' default='C%3a%5cUsers%5cDimitris%5cDesktop%5c1.2.826.0.1.3680043.2.135.734653.43121060.6.1346430.0.1.1.0.dcm' isModified='0'>C%3a%5cUsers%5cDimitris%5cDesktop%5c1.2.826.0.1.3680043.2.135.734653.43121060.6.1346430.0.1.1.0.dcm</Property>
    <Property id='FirstName' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='LastName' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='Modality' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='PatientID' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='PatientUniqueID' upperBound='' lowerBound='' default='....' isModified='0'>....</Property>
    <Property id='PatientsBirthDate' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='PatientsName' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='PatientsSex' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='ReferringPhysiciansName' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='SOPInstanceUID' upperBound='' lowerBound='' default='1.3.6.1.4.1.24930.1346697517.15724.6' isModified='0'>1.3.6.1.4.1.24930.1346697517.15724.6</Property>
    <Property id='SequenceID' upperBound='' lowerBound='' default='0' isModified='0'>0</Property>
    <Property id='SeriesDescription' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='SeriesInstanceUID' upperBound='' lowerBound='' default='1.3.6.1.4.1.24930.1346697517.19169.5' isModified='0'>1.3.6.1.4.1.24930.1346697517.19169.5</Property>
    <Property id='SortKey' upperBound='' lowerBound='' default='DocumentNumber' isModified='0'>DocumentNumber</Property>
    <Property id='StudyDate' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='StudyDescription' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='StudyInstanceUID' upperBound='' lowerBound='' default='1.3.6.1.4.1.24930.1346697517.26500.4' isModified='0'>1.3.6.1.4.1.24930.1346697517.26500.4</Property>
    <Property id='StudyTime' upperBound='' lowerBound='' default='' isModified='0'></Property>
    <Property id='TransferSyntaxUID' upperBound='' lowerBound='' default='1.2.840.10008.1.2' isModified='0'>1.2.840.10008.1.2</Property>
    </PropertySet>

  • Hi,


    indeed the data is 8 bits. I believe the auto/level window code is diabled for 8 bits data, can you compare the files as saved (e.g., using irfanview) with the files printed? Otherwise the problem is at the sending side (or is that conquest too?)


    Marcel

  • Hi,


    you managed earlier to get access to the files in printer_files (.dcm). This can be done by running dgate -v from the command line without starting the GUI. If these images have the same quality as the printed images, the loss of quality occurs on the sending side - and you will need to change things there. Setting the printer to 12 bit enables auto contrast on my side, and will lead to a less consistent print quality - so this is not the solution.


    Marcel

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