retitle 1115346 Lower bottom is cut away, and empty space added to the top right when converting PNG to PDF affects 1115346 + pngtools libimage-exiftool-perl pngcheck severity 1115346 important quit
Consider test.png in the attachment. Open it with loupe, display, or eog, and you'll see a cross in a rectangle, and there is nothing outside the rectangle. We see nothing unusual so far: $ pnginfo test.png test.png... Image Width: 100 Image Length: 166 Bitdepth (Bits/Sample): 8 Channels (Samples/Pixel): 1 Pixel depth (Pixel Depth): 8 Colour Type (Photometric Interpretation): GRAYSCALE Image filter: Single row per byte filter Interlacing: No interlacing Compression Scheme: Deflate method 8, 32k window Resolution: (not specified) FillOrder: msb-to-lsb Byte Order: Network (Big Endian) Number of text strings: 0 $ exiftool -a -G test.png [ExifTool] ExifTool Version Number : 13.25 [File] File Name : test.png [File] Directory : . [File] File Size : 493 bytes [File] File Modification Date/Time : 2026:06:02 08:02:41+02:00 [File] File Access Date/Time : 2026:06:02 08:05:45+02:00 [File] File Inode Change Date/Time : 2026:06:02 08:03:31+02:00 [File] File Permissions : -rw-rw-r-- [File] File Type : PNG [File] File Type Extension : png [File] MIME Type : image/png [PNG] Image Width : 100 [PNG] Image Height : 166 [PNG] Bit Depth : 8 [PNG] Color Type : Grayscale [PNG] Compression : Deflate/Inflate [PNG] Filter : Adaptive [PNG] Interlace : Noninterlaced [Composite] Image Size : 100x166 [Composite] Megapixels : 0.017 $ file test.png test.png: PNG image data, 100 x 166, 8-bit grayscale, non-interlaced $ pngcheck test.png zlib warning: different version (expected 1.2.13, using 1.3.1)OK: test.png (100x166, 8-bit grayscale, non-interlaced, 97.0%).
Now run magick test.png test.pdf or convert test.png test.pdf followed by $ pdfinfo test.pdf Title: test Author: https://imagemagick.org Creator: https://imagemagick.org Producer: https://imagemagick.org CreationDate: Tue Jun 2 07:46:05 2026 CEST ModDate: Tue Jun 2 07:46:05 2026 CEST Custom Metadata: no Metadata Stream: no Tagged: no UserProperties: no Suspects: no Form: none JavaScript: no Pages: 1 Encrypted: no Page size: 3964 x 6509 pts Page rot: 0 File size: 3111 bytes Optimized: no PDF version: 1.3 The page size of the PDF file is now huge. However, for the original PNG file, it was not reported by `pnginfo`, `exiftool`, `pngcheck`, or `file`, and it was not noticeable in any of the three image viewers. Open test.pdf in evince, and observe lots of free space to the right and above the rectangle with a cross. Also, the lower left part of the rectangle with a cross is missing. Clearly, this is not intended. We expect that the target PDF is visibly the same as the original PNG. If a clean conversion cannot be done or doesn't make sense, an error should be reported or the user should be warned at the very least. In retrospect, we found caNv to be the culprit. No idea which tool added this. Raising severity as this bug silently makes your life hard: you don't notice that your original PNG files are unusual until after the conversion to a PDF. It's even worse: the target PDF might have only few columns/lines missing on the left/bottom, and it might have only few white lines/columns added to the top/right; these are hard to see, and the wrong PDF might even get shipped to the receiver before you notice this error (if ever).
test.pdf
Description: Adobe PDF document
