High Efficiency Image Container (HEIC) applies H.265 (HEVC) intra-frame compression achieving roughly twice the efficiency of JPEG at equal visual quality, used natively by Apple devices. HTM file (HTM) stores data in the HTM format. This embeds the raster image inside a document container, fixing its dimensions on the page. Metadata such as creation date and embedded colour profiles is preserved where the target format supports it. The result is a standard HTM file readable by any compatible application. 1converter handles HEIC-to-HTM conversion server-side: files are uploaded over HTTPS, processed on isolated cloud infrastructure, and the converted output is available for download for 24 hours before automatic deletion. No account is required for standard conversions.