Parsing fails with non-standard APP0

[wyozi]

Some JPEGs have a non-standard APP0 segment. It is non-standard but it breaks parsing because jay-peg assumes fixed size APP0.

I can't give the original image but here's the hex for the broken segment: (includes APP0 marker, two-byte size, and the whole marker data)

0xFF,0xE0,0x00,0x14,0x4A,0x46,0x49,0x46,0x00,0x01,0x01,0x01,0x01,0x2C,0x01,0x2C,0x00,0x00,0x41,0x4D,0x50,0x46

The last four bytes spell out AMPF in ascii, which according to a random googling is somehow related to some Apple extension. See also https://github.com/exiftool/exiftool/blob/master/lib/Image/ExifTool.pm#L2226

[anddani]

@diegomura We identified an issue in the react-pdf library when users uploaded images on their iOS device from the camera roll. Images that are stored as HEIC are automatically converted to JPEG. One issue. This conversion results in a JPEG with segment length 0x14 as illustrated in this issue. Sadly we cannot make iOS not convert it from HEIC. We tracked down the error to this library which is used by react-pdf.

Strangely, uploading a picture using "Take photo" specifies a segment length of 0x10. This might be due to the camera skipping the HEIC conversion step. 🤷

The following JPEG was converted by iOS from HEIC and will not be rendered properly in a PDF using react-pdf as it has the segment length set to 0x14. Hopefully it helps.