I have a page with a gallery where users upload images. I noticed that there is one particular user who uploaded 3 tiff images and that they cannot be accessed.
Exception type: System.ArgumentException
Exception message: Parameter is not valid.
It happens here:
using (Image photo = new Bitmap(new MemoryStream(photoData)))
Files seems to be ok, sice File.ReadAllBytes() works, I can download them using other method (the one not working is used for returning a resized image only), test locally and the exception is not thrown. Any ideas what could be the case? Unfortunatelly I dont know yet if this occurs for all tiff images uploaded by other users too.
Support for TIFF flavors (and there are many of them) depends on the version of Windows on your server. More precisely, it depends on GDI+ library's version.
Without seeing the TIFFs there is nothing more I can tell. But I can recommend you to try some 3rd party libraries just for TIFF files. There is de-facto standard libtiff library and I have ported it to C# some time ago. You might try the port.
There are some samples you might be interested in. I think Convert color TIFF to a 32-bit System.Drawing.Bitmap might be most eligible for your task.
Related
I am using Ghostscript to convert pdf1.3 to pdf/a-1b using this command:
gs -dPDFA -dBATCH -dNOPAUSE -dNOOUTERSAVE -sColorConversionStrategy=sRGB -sDEVICE=pdfwrite -sOutputFile=output.pdf PDFA_def.ps input.pdf
The PDFA_def.ps is customized to use the srgb icc profile. Except that change it is the standard def file which comes with GS 9.26.
Now comes the tricky part:
1- running this conversion locally on a ubuntu 18.10, GS 9.26 it works fine an i get a valid pdf/a
2- running the same command in a docker container (ubuntu 18.10. GS 9.26) creates a pdf/a as well, which is considered to be valid
However, in the first scenario I can process the file using mustang (https://github.com/ZUGFeRD/mustangproject) to create a valid electronic invoice. In the second scenario (docker container) this fails, since the file is not considered to be valid pdf by mustang.
checking both pdf files I would have expected them to be identical since i am running the same converison on it. However they are not. The PDF create in the dockerfile is 10 bytes smaller and shows some different metainformation in the file itself.
I suspect that there must be some "hidden depdencies" that make GS to act different on my host system compared to a docker container, but it feels entirely wrong and I am running out of means to debug further.
Does anyone know, wether GS has some more depdencies that might cause the same command to produce different results?
The answer is 'maybe'. It depends on how Ghostscript was built for starters.
I assume you are using a package, and not building from source yourself. In which case there are a number of dependencies including; FreeType, LibJPEG, JBIG2dec, LibTIFF, JPEG-XR, LCMS2, LibPNG, OpenJPEG, Expat, zlib, potentially IJS, CUPS and X-Windows, depending on what devices were built in.
Any or all of these could be system shared libraries instead of being built using the specific version shipped by Artifex. They could also be different versions on the two systems.
That said, I think its 'unlikely' that this is your problem. However, without seeing the PDF files I can't tell you why there is a difference. Differences in the metadata are to be expected, since that includes a date/time stamp.
I'd really need to see examples of the original and the two output PDF files to be able to comment further.
[Edit]
Looking at the files they have been produced compressed (unsurprisingly) which can obviously lead to differences in size if there are small differences in the input streams. So the first task was to decompress the files.
That done I see there are, essentially, no differences between them. One of the operating systems is using a time zone 7 hours behind UTC, the other is in UTC so where one of the systems is time stamping with (eg)
2019-04-26T19:49:01Z
The other is using
2019-04-26T12:51:35-07:00
So instead of Z (for UTC) you get -07:00 which is where the extra 10 bytes are coming from. Other than that, the Unique IDs are (as you would imagine) different, the Length values for the streams are different for the streams containing dates, and the startxref is different because the streams are different lengths.
Both files claim to be compatible with PDF/A-1b. In short I can see no real differences between them. Since you are using a tool to further process the files, I'd suggest you try taking the PDF file from your working system and try processing it on the non-working system, and vice versa, it seems to me that the problem may be the later processing rather than the PDF file itself. Perhaps you have different versions of that tool on the two systems.
For what it may be worth, Ghostscript can be induced into creating a ZUGFeRD file directly, see this bug report and this commit to the repository.
Im working on reducing noise from noisy image in OPENCV using different filters. i want to know that how i capture or save the result images during debugging code?
You can:
Save with imwrite all your debugging images, better in a specific folder.
Use Image Watch which will enable you to see all your Mat in a nice and powerful viewer during debugging. Just download and install it. You can access the Image Watch viewer in VS: View -> Other Windows -> Image Watch
I recommend the second approach, which personally I find very useful.
Have a look also at this answer.
If you can use CLion instead Visual Studio you can utilize the OpenCV Image Viewer plugin, which displays matrices while debugging with just one click. There is also an option to save the image on a disk.
https://plugins.jetbrains.com/plugin/14371-opencv-image-viewer
Disclaimer: I'm the author of this plugin
I'd like to know of alternatives to the command line program texturetool which comes with XCode for converting PNG Images to PowerVR compressed images.
For some reason texturetool takes about 50 seconds for converting some of the images I am working with. With about 1.3 mio images to be compressed, that would take several months.
Now I am looking for other tools running on either Linux or OSX, most preferable an in-memory C++ library, as the images are being generated procedurally.
Would love to get an answer.
Thanks.
Imagination Technologies have just released an updated version of their texture compression library That may be worth trying. (I know the page only says Windows and Linux but there appears to be a Mac version there as well).
I recently discovered that the PDFs exported by the Fast Report's PDF export filter aren't displayed correctly in Mac OSX, iOS and Android devices.
Fast Report informed that their pdf implementation only support Windows and they can't say when the new implementation that they are working on will be available.
I also tried to use the Gnostice export filter, but their demo installer didn't work in Delphi XE and when I contacted them, they took 15 days to send me some attached dcus which also didn't work. So I'm searching for another option.
If you know or use a PDF export filter which works with Fast Report, please let me know.
November 2015: Fast Report now have PDF/A support, with this option enabled the PDFs are fine on all platforms.
October 2014 - Fast Report 5 still seems to generate "Windows-only" PDF. A production-ready solution for this problem would be a benefit for cross-platform developers, given that Fast Report is the report generator bundled with Delphi.
Here is a fresh example generated with the Fast Report 5 demo, displayed with Adobe Reader 11 on Android 4.4:
And on Windows:
Fast Report informed that their pdf implementation only support Windows and they can't say when the new implementation that they are working on will be available.
I'm not sure that should be taken literally, considering PDF is supposed to be a cross platform format. It more likely means they don't actually have the time, equipment or expertise to test with those platforms. The PDF export filter that I'm using is the one built into Fast Report! It surely has some bugs, but I managed to work around them. And I think that might also work for you: Start with a simple document that does export properly, start adding features until it brakes, then you know what brakes it and you'll know how to work around the problem.
From my experience, here's what got me into trouble:
Rounded corners in the PDF document didn't look like the ones in the Fast Report preview. My fix: Found a combination of settings that made the exported PDF look exactly like the preview document. For me rounded corners were just a cosmetic feature, and with cosmetics there's no "One Look"; The alternative worked just fine. This might actually be fixed in the most recent version, but I didn't bother changing the document to test.
Transparency issues and outline issues. When working with the Fast Report editor (and when looking at it's previews) it's easy to overlap objects. You don't see this because of the object opacity. When exporting to PDF overlapped objects somehow managed to "print" outlines, and it obviously looked ugly. My fix: pay closer attention to those objects, make sure they don't overlap or make sure they don't generate outlines if no outlines are supposed to be seen.
Also make sure you test using ADOBE Reader, on any of the given platforms. If it works with the Adobe reader but doesn't work with other readers, there might be a bug in the 3rd party reader!
Edit: Here (link) is a sample PDF document generated by my Fast Reports application. I have no idea what kinds of documents you generate, but in my book that's a mighty complex document. Notice the diagonal line that starts where the table data ends, notice the embedded images (bar code, stamp, signature).
I opened that document on the following mobile devices:
iPad, running iOS: The document renders 90% ok. Images are not rendered at all, but they're not important to my document (and that's very likely a problem with the iOS reader). All the fancy colored lines and rounded corners are properly rendered. Some text is not properly rendered, and I'm pretty sure that didn't render because the "box" that contains it is too small for the contents. That most likely happens because I didn't embed the TTF fonts into the PDF and the Apple font on iOS didn't perfectly match the Microsoft font that was used on Windows.
Samsung Galaxy S2, running Android 2.3: The document renders 100% correctly.
Samsung Something(??), running Windows Mobile 6.5 and the FoxReader: The document is totally gibberish: pictures showed up but the spacing between letters was messed so bad it's impossible to read. I blame the reader, it's not Acrobat and it probably wanted to be "smart". And it broke it's teeth in my text encoding, because my text is not English.
About the PDF format: A document is "PDF" if it conforms to the standard, here's some Wikipedia info on that. In theory a PDF document should render exactly the same way any way you look at it, but there are forces at play that might work against this:
Not all readers are "Adobe Acrobat". In theory they're all compatible, in practice they're most like not 100% compatible.
PDFs that don't embed fonts depend on the fonts available on the host system. If they're not the exact same fonts there's trouble ahead, because they might have slightly differing sizes. Since we're talking about PDF's that were generated on Windows and opened on iOS or Android, those are obviously different platforms and they're guaranteed to use different fonts (because fonts are licensed, and I doubt Microsoft will licence it's fonts to Apple. I also doubt Apple would want Microsoft fonts). One possible solution is embedding fonts, but that makes your PDF files significantly larger.
AFAIK you can export your Fast Report pages as metafiles (i.e. vectorial Windows format, which is in fact a raw serialization of GDI commands).
Then you could be able to render those metafiles into PDF using our Open Source SynPDF library. It works from Delphi 5 up to XE, is Unicode ready, can embed true type fonts, and even create PDF/A files.
It is also able to export metafiles included in reports as vectorial pictures (and not bitmaps), and could therefore highly increase the pdf quality and at the same time shrink its size.
See for instance how it can be used for QuickReport. A similar technical should be used with Fast Report.
The Gnostice support answered my e-mail which I reported that their trial installer didn't work and send me some tips about which could be the problem and I was able to install it.
The company I work for already bought me a license and I already replaced the Fast Report Export Filter, which was a task as simple as droping 2 components on the same Form as the frxReport Object and setting 2 or 3 properties.
Also, to export the report programatically was also 2 lines of code and the information was easily found in their FAQ.
In the end, based on the recomendations and after looking for other options just to find abandoned components which doesn't have any updates for years, the Gnostice eDocEngine was the best solution.
Just hope they make their installer a little more "Programmer Friendly" as if it had complained about the lack of Fast Report's units in the search path I would've been able to at least have an idea of what was going on, instead of just getting an error and blaming them for having a trial installer which didn't work.
After replacing the filter and generating the PDF's using the eDocEngine component, the PDFs now work the same in iOS, OSX and Android.
Here is my workaround solution. It's not an universal one, but helped me in my case.
The main idea: use in report font with small file size (I've found Arial-like font with cyrillic charset with size 57kb). So the exported files can be 100-200 kb.
Details is here:
http://dev-doc.blogspot.com/2013/03/fastreport-4-font-reading-and-huge-file.html
I use wPDF from WPcubed components, it's really a great product, good value for money
You can always install one of the PDF printers. These are in fact PDF convertors that install as windows printer. They work from any application including FastReprt components - just print on them.
Creating a ruby on rails site that uses RMagick to create thumbnails for many types of images. RMagick cannot read dwg files however.
I've tried a few things, looked into the Java library JDWGLib, which would probably allow me to write a converter, but it would be a total from the ground up solution, where I just need a thumbnail.
Also considered using a viewer program to open the file in a remote X session and do a screen capture, however I'm not sure how I could ever guarantee that the viewer had completed opening when I took the screenshot.
I'm not concerned with being able to manipulate the file other than to create the thumbnail. It is going to be used for commercial purposes, so any libraries used need to be compatible.
cad2svg is a simple Linux command-line utility that automatically converts AutoCAD files (both dwg and dxf) to SVG.
the link
I could not find any command-line-able tool for making thumbnails, on either windows or linux.
I guess you could download the DWGdirect lib (C++) wich allows the exportation of a DWG to a bitmap... but this requires purchasing a membership license on the """Open""" Design Aliance.
I would recommend adding an additional file input on your form that says "thumbnail". And let the users provide the screenshots.