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"markdown": "HEIC is HEVC (H.265) intra-frame coding stored in a HEIF container. It is the default photo format on iPhones and iPads (Settings ▸ Camera ▸ Formats ▸ High Efficiency), and it is noticeably smaller than JPEG at similar quality. Outside Apple's ecosystem it is awkward: HEVC is patent-encumbered, so browsers, most Windows installs and many web services do not decode it.\n\nFor anything you publish, convert it. [AVIF](/codecs/images/avif/) uses the same HEIF container with royalty-free AV1 and has far wider support, and [JPEG XL](/codecs/images/jxl/) and [JPEG](/codecs/images/jpeg/) cover the other cases. HEIC is a capture and interchange format: read it and convert it, don't author it for the web.\n\n## Format basics\n\n- **HEIF** (ISO/IEC 23008-12) is the container: a primary image, thumbnails, auxiliary images (alpha, depth), grids of tiles, collections, transformations (rotate, crop, mirror), metadata (Exif, XMP, ICC/nclx) and image sequences. **HEIC** is HEIF carrying HEVC. HEIF can also carry AV1 (AVIF), AVC, JPEG, VVC and others.\n- **HEVC profiles.** Phones use Main (8-bit 4:2:0) or Main 10 (10-bit 4:2:0, used for HDR). 4:2:2 and 4:4:4 need range-extension profiles that many hardware decoders and viewers lack.\n- **Lossless exists** (HEVC lossless tools), but it is not widely used and files are large; use PNG or JPEG XL.\n- **Alpha and depth** are separate auxiliary image items, not a fourth channel. Exporters and converters often drop them, and a plain converted copy loses portrait-mode depth maps and Live Photo relationships.\n- Not royalty-free. HEVC is licensed through patent pools such as [Access Advance](https://accessadvance.com/licensing-programs/hevc-advance/) and others, and some patent holders are not in any pool. Apps that use the operating system's codec rely on the OS vendor's licence; an app that ships its own HEVC decoder or encoder may need its own. libheif is LGPL, x265 is GPL, and neither licenses the patents.\n\n## Support\n\n| Platform | HEIC |\n| ------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Safari, iOS, macOS | Safari 17+ displays HEIC ([Safari 17 notes](https://webkit.org/blog/14445/webkit-features-in-safari-17-0/)); the OS and Photos have supported it for years. |\n| Chrome, Edge, Firefox | No `![]()
` support ([caniuse](https://caniuse.com/heif)); serve a JPEG/AVIF/WebP version. |\n| Android | Decoding since Android 9 (device optional; 10-bit also needs HEVC Main 10), encoding via `MediaCodec`/`HeifWriter` from Android 10 ([supported formats](https://developer.android.com/media/platform/supported-formats)). |\n| Windows | Needs the HEIF Image Extensions and HEVC Video Extensions from the Microsoft Store. |\n| Linux | Via libheif with libde265 or FFmpeg for decoding; most distributions package it. |\n\nSee [image and audio support](/reference/image-audio-support/) for how to test a given file. Upload forms, CDNs and CMSes frequently reject HEIC even when the OS opens it.\n\n## Convert and encode with libheif\n\n[libheif](https://github.com/strukturag/libheif) provides `heif-enc`, `heif-dec` and `heif-info`. Codecs are plugins: `heif-enc --list-encoders` shows what your build has (x265 for HEVC; aom, SVT-AV1 and rav1e for AVIF).\n\n```sh\nheif-dec photo.heic photo.jpg\nheif-dec -q 90 photo.heic photo.jpg\nheif-enc -q 75 input.png output.heic\nheif-info output.heic\n```\n\n`heif-dec` chooses the output format from the extension (jpg, png, tif, webp, y4m); `-q` is the JPEG quality. `heif-enc` defaults to HEVC through x265 at quality 50; its quality scale is not comparable to JPEG's or AVIF's, so pick a value by eye.\n\n| Option | What it does |\n| --------------------------------- | --------------------------------------------------------------------------------------------------------- |\n| `-q 0..100` | Lossy quality (default 50). |\n| `-L` | Lossless; also switches to RGB (identity matrix) so pixels survive. |\n| `-p chroma=444` | x265 plugin chroma format (420 default, also 422 or 444). |\n| `-b 9..16` | Bit depth taken from a **16-bit PNG** input (default 10); 8-bit inputs stay 8-bit. |\n| `-p preset=…`, `-p tune=…` | x265 preset (default `slow`) and tune (default `ssim`; also `psnr`, `grain`, `fastdecode`). |\n| `-p x265:KEY=VALUE` | Pass any x265 parameter through. |\n| `-A` / `--avif` | Encode AVIF instead; the AV1 plugin parameters are in the [AVIF page](/codecs/images/avif/). |\n| `--color-profile`, `--clli` | Set nclx colour signalling and HDR light-level metadata. |\n| `-t N`, `--no-alpha` | Embed a thumbnail of maximum size N; drop alpha. |\n| `-S`, `--sequence` | Write an image sequence (animation) from several inputs. |\n\nImageMagick (`magick in.heic out.jpg`) and many photo tools use libheif underneath.\n\n## Pitfalls\n\n- **Grids.** Phone photos are often stored as a grid of tiles; naive extractors give you only one tile. Use libheif-based tools.\n- **Metadata on conversion.** Exif, ICC and HDR information survive only if the converter carries them over. Check orientation and colour after converting.\n- **HDR.** Apple's HDR photos carry an extra gain-map image; a converter that ignores it gives you only the SDR rendering.\n- **Chroma.** HEVC for stills is almost always 4:2:0. If you encode screenshots, coloured text or line art, use `-p chroma=444` or a different format.\n- **Licensing for software.** Shipping x265-based encoding in a closed-source or commercial product has GPL and patent implications; AVIF avoids both.\n\n## Related pages\n\n- [AVIF](/codecs/images/avif/) is the royalty-free AV1 sibling in the same container and the usual target format.\n- [HEVC](/codecs/video/hevc/) is the video codec underneath.\n- [JPEG XL](/codecs/images/jxl/) covers HDR and lossless without patents.\n- [x265](/tools/software-encoders/x265/) is the encoder behind `heif-enc`.\n\n## Full option reference\n\nThe tables below are the full `heif-enc` and plugin parameter references for libheif 1.23.6. [Reading option tables](/reference/encoder-parameters/) explains the Default column.\n\n## heif-enc 1.23.6 complete frontend reference\n\n\nINPUT to --avc
\n\n| Parameter / aliases | Type or accepted values | Default | Purpose and constraints |\n| ------------------- | ----------------------------- | ------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------- |\n| `INPUT` | path(s) | required for encoding | One or more input images. Several inputs go into one file as separate images, not an animation (use --sequence for that). |\n| `OUTPUT` | optional path | derived from first input | Output file. The suffix (.heic, .avif) picks the codec when no codec switch is given. |\n| `--help`, `-h` | action | not requested | Print usage. Hides several registered switches that are listed below. |\n| `--version`, `-v` | action | not requested | Print the heif-enc and libheif versions. Lowercase -v is not verbose. |\n| `--quality`, `-q` | integer 0–100 | 50 | Lossy quality passed to the selected encoder plugin. Not comparable across plugins or with avifenc. |\n| `--output`, `-o` | path | derived from first input | Output filename. Without it, the name is derived from the first input. |\n| `--lossless`, `-L` | flag | false | Lossless coding with identity matrix (RGB). Plugins without lossless support fall back to lossy with a warning. |\n| `--thumb`, `-t` | positive maximum dimension | 0: disabled | Add a thumbnail whose longer side is at most this many pixels. |\n| `--verbose` | repeatable flag | 0 repetitions | More codec logging. Repeat for more detail. |\n| `--params`, `-P` | action | not requested | List the selected plugin's parameters and exit. |\n| `--no-alpha` | flag | false: master alpha saved | Drop the alpha channel from the main image. |\n| `--no-thumb-alpha` | flag | false: thumbnail alpha saved | Drop the alpha channel from the thumbnail only. |\n| `--list-encoders` | action | not requested | List the encoder plugins in this build, per codec. |\n| `--encoder`, `-e` | plugin ID | highest-priority plugin for the codec | Pick an encoder plugin by ID from --list-encoders (for example x265, aom, svt, rav1e). |\n| `--bit-depth`, `-b` | integer 9–16 | 10 | Bits kept from 16-bit PNG or TIFF input (9–16). The encoder plugin limits the coded depth (x265: 8, 10 or 12). |\n| `--avif`, `-A` | flag | false | Encode as AVIF (AV1). Not needed when the output name ends in .avif. |\n| `--hevc` | flag | false (HEVC is the fallback) | Encode as HEVC (HEIC). HEVC is also used when no codec flag is given and the output suffix names no other codec. |\n| `--vvc` | flag | false | Encode VVC. Experimental; needs a VVC plugin. |\n| `--avc` | flag | false | Encode AVC (H.264, x264 plugin). Experimental. |\n\n \n\n\n--jpeg to --benchmark
\n\n| Parameter / aliases | Type or accepted values | Default | Purpose and constraints |\n| --------------------------- | ---------------------------------------- | ---------------------------- | ---------------------------------------------------------------------------------------------------- |\n| `--jpeg` | flag | false | Store JPEG-coded data inside HEIF. This does not write a plain .jpg. |\n| `--jpeg2000` | flag | false | Store JPEG 2000 data inside HEIF. Experimental; needs an OpenJPEG plugin. |\n| `--htj2k` | flag | false | Store High Throughput JPEG 2000 data inside HEIF. Experimental; needs an OpenJPH plugin. |\n| `--uncompressed`, `-U` | build-gated flag | false | Store raw pixels (HEIF uncompressed codec). Only in builds with WITH_UNCOMPRESSED_CODEC. |\n| `--unci-compression-method` | none, brotli, deflate, zlib | zlib | Compression for uncompressed-codec payloads. Needs an uncompressed-codec build. |\n| `--component-content-ids` | build-gated flag | false | Write component content IDs for uncompressed images. Needs uncompressed and experimental builds. |\n| `--color-profile` | custom, auto, compatible, 601, 709, 2020 | custom | NCLX preset: custom uses the flags below, auto guesses from the input, compatible avoids rarely implemented values, 601/709/2020 are fixed presets. |\n| `--matrix_coefficients` | H.273 integer | 6 | NCLX matrix coefficients (H.273) for the custom profile. 6 is BT.601; --lossless forces 0 (identity). |\n| `--colour_primaries` | H.273 integer | 1 | NCLX colour primaries (H.273) for the custom profile. 1 is BT.709/sRGB. |\n| `--transfer_characteristic` | H.273 integer | 13 | NCLX transfer characteristics (H.273) for the custom profile. 13 is sRGB. |\n| `--full_range_flag` | 0 or 1 | 1 | NCLX range for the custom profile: 1 full range, 0 limited. |\n| `--enable-two-colr-boxes` | flag | false | Write both ICC and NCLX profiles when the input has both. |\n| `--clli` | two 16-bit unsigned values | absent | Set MaxCLL,MaxPALL (cd/m², 16-bit values) content light level metadata. Metadata only; no HDR conversion. |\n| `--pasp` | two unsigned spacing values | absent | Set pixel aspect ratio as h,v. Metadata only; pixels aren't resampled. |\n| `--premultiplied-alpha` | flag | false | Tell the encoder the input alpha is already premultiplied. Doesn't premultiply the input. |\n| `--rotate-cw` | 0, 90, 180 or 270 | 0 | Store a clockwise rotation (0, 90, 180, 270) as a transform; pixels are not rewritten. |\n| `--flip-h` | flag | false | Store a horizontal flip as a transform. |\n| `--flip-v` | flag | false | Store a vertical flip as a transform. |\n| `--plugin-directory` | directory path | default plugin path | Load encoder plugins from this directory in addition to the default search path. |\n| `--benchmark` | flag | false | Print encoding time, PSNR and output size. |\n\n \n\n\n--enable-metadata-compression to --metadata-track-uri
\n\n| Parameter / aliases | Type or accepted values | Default | Purpose and constraints |\n| ------------------------------- | ---------------------------------------- | --------------------------------------- | ----------------------------------------------------------------------------------------------- |\n| `--enable-metadata-compression` | auto, off, deflate, zlib, brotli | off | Compress metadata items. Experimental; listed in --help only in builds with header compression. |\n| `--pitm-description` | text | empty | Text description attached to the primary image. Experimental. |\n| `--chroma-downsampling`, `-C` | nn, nearest-neighbor, average, sharp-yuv | average (preferred, not forced) | RGB-to-YUV chroma downsampling: nn (nearest-neighbor), average or sharp-yuv (needs libsharpyuv). Without -C, libheif prefers average but may use another method; -C forces the choice. |\n| `--cut-tiles` | positive side length | 0: disabled | Split the input into square tiles of this many pixels per side and store it as a tiled image. |\n| `--tiled-input`, `-T` | flag | false | Read a tile set from numbered files (for example tile-01-05.jpg); give one filename and the rest are found. |\n| `--tiled-image-width` | positive pixels | 0: infer from tiles | Override the total width of a tiled image, in pixels. |\n| `--tiled-image-height` | positive pixels | 0: infer from tiles | Override the total height of a tiled image, in pixels. |\n| `--tiled-input-x-y` | flag | false: filename numbers are y,x | Read the first number in tile filenames as x instead of y. |\n| `--tiling-method` | grid; build-gated unci/tili | grid | How tiles are stored: grid items, tili (experimental builds) or unci (builds with the uncompressed codec). |\n| `--add-pyramid-group` | flag | false | Put several input images into a multi-resolution pyramid group. Experimental; listed in --help only in experimental builds. |\n| `--sequence`, `-S` | flag | false | Encode a timed image sequence; a numbered filename pulls in all files with that pattern. |\n| `--video`, `-V` | flag | false | Use a video track handler for sequence output. |\n| `--timebase` | positive ticks per second | 30 | Sequence clock in ticks per second. |\n| `--duration` | positive ticks per frame | 1 | Frame duration in ticks. Seconds per frame = duration ÷ timebase. |\n| `--fps` | positive frame rate | unset | Set timebase and duration from a frame rate. 29.97 maps to 30000/1001; other fractions are rounded on a 90000-tick clock. |\n| `--repetitions` | positive integer or infinite | 1 | How many times playback repeats, or infinite. 0 is rejected. |\n| `--max-frames` | positive integer | 0: no limit | Stop after this many frames. 0 is rejected. |\n| `--vmt-metadata` | build-gated file path | none | Video metadata track input file. Experimental; needs an experimental-features build. |\n| `--binary-metadata-track` | build-gated flag | false | Write the metadata track as binary. Experimental. |\n| `--metadata-track-uri` | build-gated URI | vmt:metadata | URI identifying the metadata track. Experimental. |\n\n \n\n\n--add-mime-item to --
\n\n| Parameter / aliases | Type or accepted values | Default | Purpose and constraints |\n| ------------------------- | ------------------------------------------------------- | --------------------------------------------- | ----------------------------------------------------------------------------------------- |\n| `--add-mime-item` | build-gated MIME type | none | Attach a generic MIME item of this type. Experimental. |\n| `--mime-item-file` | build-gated payload path | none | File holding the payload for --add-mime-item. Experimental. |\n| `--mime-item-name` | build-gated text | empty | Name for the MIME item. Experimental. |\n| `--turtle` | build-gated file path | none | Read RDF Turtle content-ID relationships from a file. Experimental. |\n| `--embed-turtle` | build-gated flag | false | Embed the --turtle file as an item. Experimental. |\n| `--gop-structure` | intra-only, low-delay/p, unrestricted/b | low-delay | Prediction structure for sequences: intra-only, low-delay (P) or unrestricted (B). The plugin must support it. |\n| `--min-keyframe-distance` | nonnegative integer | 0: undefined | Minimum frames between keyframes in a sequence. 0 leaves it to the encoder. |\n| `--max-keyframe-distance` | nonnegative integer | 0: undefined | Maximum frames between keyframes in a sequence. 0 leaves it to the encoder. |\n| `--set-gimi-track-id` | text ID | none | GIMI track ID for the visual track of a sequence. Experimental; listed in --help only in experimental builds. |\n| `--sai-data-file` | file path | none | File with SAI (sample auxiliary information) data for sequence frames. Listed in --help only in experimental builds. |\n| `--omaf-image-projection` | equirectangular or cube-map | absent | Mark the image as equirectangular or cube-map for OMAF viewers. Doesn't warp pixels. |\n| `--add-compatible-brand` | four-character brand, repeatable | no added brands | Add a four-character compatible brand to the file. Repeatable; only add brands the file really conforms to. |\n| `--unif` | flag | false | Use one ID namespace for items and tracks and add the unif brand. |\n| `--mini` | flag | false | Use the compact mini box layout. Readers need explicit support. |\n| `--raw` | flag | false | Treat the input as raw pixel data even without a .raw/.img suffix. |\n| `--raw-width` | positive pixels | 0: derived from file size | Raw input width in pixels. Give width, height or both; a missing one is computed from the file size. |\n| `--raw-height` | positive pixels | 0: derived from file size | Raw input height in pixels. Give width, height or both; a missing one is computed from the file size. |\n| `--raw-type` | uint8/sint8/uint16/sint16/uint32/sint32/float32/float64 | none | Raw sample type: uint8, sint8, uint16, sint16, uint32, sint32, float32 or float64. Required for raw input. |\n| `--raw-endian` | little or big | little | Byte order of raw samples, little or big. |\n| `-p` | NAME=VALUE, repeatable | none | Set an encoder plugin parameter as NAME=VALUE. Repeatable; prefix with the encoder name (x265:ctu=64) to reach the library's own options. |\n| `--` | separator | not used | End of options; everything after is an input filename. |\n\n \n\n### libheif x265 plugin parameters\n\n| Parameter / aliases | Type or accepted values | Default | Purpose and constraints |\n| ------------------- | ----------------------------- | ------------------------------- | -------------------------------------------------------------------------------- |\n| `quality` | integer 0–100 | 50 | Lossy quality, mapped to x265 CRF. |\n| `lossless` | boolean | false | x265 lossless mode. Use chroma=444 for exact RGB. |\n| `preset` | x265 preset name | slow | x265 speed preset. Slower presets compress better. |\n| `tune` | psnr, ssim, grain, fastdecode | ssim | x265 tune. ssim is the plugin default, not x265's own default. |\n| `tu-intra-depth` | integer 1–4 | 2 | Maximum intra transform-unit split depth. Higher is slower. |\n| `complexity` | integer 0–100 | unset | Extra effort, 0–100: 60+ enables rd 6 and rd-refine, 70+ cu-lossless, 90+ turns off WPP. Slower for small gains. |\n| `chroma` | 420, 422 or 444 | 420 | Chroma subsampling of the coded image. |\n\n### Optional libheif Kvazaar plugin parameters\n\n| Parameter / aliases | Type or accepted values | Default | Purpose and constraints |\n| ------------------- | ----------------------- | ------- | ------------------------------------------------------------------------------------------------------------------------ |\n| `quality` | integer 0–100 | 50 | Lossy quality. |\n| `lossless` | boolean | false | Lossless mode. The plugin only accepts 4:2:0 for colour input, so RGB isn't preserved exactly. |\n"
}