Convert RAW DNG images and screenshots to HEIC

For those who deal with lots of RAW DNG images, screenshots, large JPEGs: this shortcut will neatly convert them into much smaller iOS-native HEIC images (compatible with Win10/11) and save lots of space.

- PNG screenshots to HEIC: 4-9 to 0.2-0.3 Mb

- DNG to HEIC (12 Mpix): 20-30 to 1-3 Mb.

- DNG to HEIC (48 Mpix): not tested, please give a feedback.

Choose your images, tap "Share", tap "HEIC and delete". You will be prompted whether you'd like to continue (1), pick your album to save (2), and delete original files (3).

Image-only files are processed; videos and HEIC files are ignored.

If you're using apps like Lightroom to process RAW images, then you'll be able to convert Lightroom's exported JPEGs to HEIC and delete those JPEGs along with DNG source files, retaining a copy of each JPEG and DNG.

If you don't need Lightroom-like apps, this shortcut converts DNGs directly to HEIC. In such a case, the default Iphone's image processing will be applied. Thus, starting from iPhone 14 Pro series - users can easily have 48Mpix images in small sizes, shoot in RAW and convert. 

Tips: 

- Conversion of small-sized and super-low-quality JPEGs has no benefit on file sizes.

- Type 'RAW' in Photos app to find images in RAW DNG format.

Issues: 

- As of iOS 16.0.2, burst-shot JPEGs generate a shortcut error, even if saved as a single-image JPEG.