JPEG is the language of everyday photo loops
JPG and JPEG are the same pipeline
JPG to GIF is not a different codec from JPEG — only the extension differs. Multi-select an album, reorder on the timeline, encode locally. There is no Convertify4u cloud gallery. Batch here means one coherent set per encode, not a silent farm of hundreds of unrelated files. Stay near 30 frames.
Photos will band; that is the format
JPEG has no alpha channel. If you need a sticker cutout, start from PNG and read the transparent spoke. For camera stills, raise quality, crop dead sky, and keep faces large. Megapixel dumps should be resized toward ~1200px before encode so the tab does not labor.
HEIC mislabeled as JPG
iPhone shares sometimes keep HEIC behind a .jpg name. If a still will not decode, run HEIC→JPG or HEIC→PNG, then return. Live Photo bundles are not a source. Nothing uploads to Convertify4u on the final encode.