What format is image12
, why has it no file ending? According to the documentation, it has to be one of the following:
- Windows bitmaps - *.bmp, *.dib (always supported)
- JPEG files - *.jpeg, *.jpg, *.jpe (see the Notes section)
- JPEG 2000 files - *.jp2 (see the Notes section)
- Portable Network Graphics - *.png (see the Notes section)
- Portable image format - *.pbm, *.pgm, *.ppm (always supported)
- Sun rasters - *.sr, *.ras (always supported)
- TIFF files - *.tiff, *.tif (see the Notes section)
Furthermore the documentation states, that when an image cannot be read, imread
returns an empty matrix. This could be the case in your problem.