KVAZAAR(1)

📦
version 2.3.2 · 2 versions
, in arch rolling, nixpkgs unstable, ubuntu resolute, ubuntu stonking

👑 KVAZAAR(1) 👑

🌈 User Commands 🌈

okay bestie, welcome to the group chat for kvazaar — the open source HEVC encoder that's genuinely iconic.

💖 NAME 💖

kvazaar — open source HEVC encoder

🦋 SYNOPSIS 🦋

kvazaar -i <input> --input-res <width>x<height> -o <output>

✨ DESCRIPTION ✨

okay so here's the whole menu. Required stuff first, because you literally cannot run this without them.

🌸 Required 🌸

  • -i, --input <filename> — Input file. the source, the material, the main character.
  • --input-res <res> — Input resolution [auto]
    • auto: Detect from file name.
    • <int>x<int>: width times height
  • -o, --output <filename> — Output file. where the encoded magic goes.

🎀 Presets 🎀

  • --preset <preset> — Set options to a preset [medium]
    • ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow, placebo

🍓 Input 🍓

  • -n, --frames <integer> — Number of frames to code [all]
  • --seek <integer> — First frame to code [0]
  • --input-fps <num>[/<denom>] — Frame rate of the input video [25]
  • --source-scan-type <string> — Source scan type [progressive]
    • progressive: Progressive scan
    • tff: Top field first
    • bff: Bottom field first
  • --input-format <string> — P420 or P400 [P420]
  • --input-bitdepth <int> — 8-16 [8]
  • --loop-input — Re-read input file forever. it's giving infinite loop realness.
  • --input-file-format <string> — Input file format [auto]
    • auto: Check the file ending for format
    • y4m (skips frame headers)
    • yuv

✨ Options ✨

  • --help — Print this help message and exit.
  • --version — Print version information and exit.
  • --(no-)aud — Use access unit delimiters. [disabled]
  • --debug <filename> — Output internal reconstruction.
  • --(no-)cpuid — Enable runtime CPU optimizations. [enabled]
  • --hash <string> — Decoded picture hash [checksum]
    • none: 0 bytes
    • checksum: 18 bytes
    • md5: 56 bytes
  • --(no-)psnr — Calculate PSNR for frames. [enabled]
  • --(no-)info — Add encoder info SEI. [enabled]
  • --(no-)enable-logging — Enable logging for regular encoder performance, error messages are always disblayed. [enabled] (yes, "disblayed" is exactly what it says, bestie 😭)
  • --crypto <string> — Selective encryption. Crypto support must be enabled at compile-time. Can be on or off or a list of features separated with a +. [off]
    • on: Enable all encryption features.
    • off: Disable selective encryption.
    • mvs: Motion vector magnitudes.
    • mv_signs: Motion vector signs.
    • trans_coeffs: Coefficient magnitudes.
    • trans_coeff_signs: Coefficient signs.
    • intra_pred_modes: Intra prediction modes.
  • --key <string> — Encryption key [16,213,27,56,255,127,242,112,97,126,197,204,25,59,38,30]
  • --stats-file-prefix — A prefix used for stats files that include bits, lambda, distortion, and qp for each ctu. These are meant for debugging and are not written unless the prefix is defined.

🦋 Video structure 🦋

  • -q, --qp <integer> — Quantization parameter [22]
  • -p, --period <integer> — Period of intra pictures [64]
    • 0: Only first picture is intra.
    • 1: All pictures are intra.
    • N: Every Nth picture is intra.
  • --vps-period <integer> — How often the video parameter set is re-sent [0]
    • 0: Only send VPS with the first frame.
    • N: Send VPS with every Nth intra frame.
  • -r, --ref <integer> — Number of reference frames, in range 1..15 [4]
  • --gop <string> — GOP structure [16]
    • 0: Disabled
    • 8: B-frame pyramid of length 8
    • 16: B-frame pyramid of length 16
    • lp-<string>: Low-delay P/B-frame GOP (e.g. lp-g8d4t2, see README)
  • --intra-qp-offset <int> — QP offset for intra frames [-51..51] [auto]
    • N: Set QP offset to N.
    • auto: Select offset automatically based on GOP length.
  • --(no-)open-gop — Use open GOP configuration. [enabled]
  • --cqmfile <filename> — Read custom quantization matrices from a file.
  • --scaling-list <string> — Set scaling list mode. [off]
    • off: Disable scaling lists.
    • custom: use custom list (with --cqmfile).
    • default: Use default lists.
  • --bitrate <integer> — Target bitrate [0]
    • 0: Disable rate control.
    • N: Target N bits per second.
  • --rc-algorithm <string> — Select used rc-algorithm. [lambda]
    • lambda: rate control from: DOI: 10.1109/TIP.2014.2336550
    • oba: DOI: 10.1109/TCSVT.2016.2589878
  • --(no-)intra-bits — Use Hadamard cost based allocation for intra frames. Default on for gop 8 and off for lp-gop
  • --(no-)clip-neighbour — On oba based rate control whether to clip lambda values to same frame's ctus or previous'. Default on for RA GOPS and disabled for LP.
  • --(no-)lossless — Use lossless coding. [disabled]
  • --mv-constraint <string> — Constrain movement vectors. [none]
    • none: No constraint
    • frametile: Constrain within the tile.
    • frametilemargin: Constrain even more.
  • --roi <filename> — Use a delta QP map for region of interest. Reads an array of delta QP values from a file. Text and binary files are supported and detected from the file extension (.txt/.bin). If a known extension is not found, the file is treated as a text file. The file can include one or many ROI frames each in the following format: width and height of the QP delta map followed by width * height delta QP values in raster order. In binary format, width and height are 32-bit integers whereas the delta QP values are signed 8-bit values. The map can be of any size and will be scaled to the video size. The file reading will loop if end of the file is reached. See roi.txt in the examples folder.
  • --set-qp-in-cu — Set QP at CU level keeping pic_init_qp_minus26. in PPS and slice_qp_delta in slize header zero.
  • --(no-)erp-aqp — Use adaptive QP for 360 degree video with equirectangular projection. [disabled]
  • --level <number> — Use the given HEVC level in the output and give an error if level limits are exceeded. [6.2]
    • 1, 2, 2.1, 3, 3.1, 4, 4.1, 5, 5.1, 5.2, 6, 6.1, 6.2
  • --force-level <number> — Same as --level but warnings instead of errors.
  • --high-tier — Used with --level. Use high tier bitrate limits instead of the main tier limits during encoding. High tier requires level 4 or higher.
  • --(no-)vaq <integer> — Enable variance adaptive quantization with given strength, in range 1..20. Recommended: 5. [disabled]

🔥 Compression tools 🔥

  • --(no-)deblock <beta:tc> — Deblocking filter. [0:0]
    • beta: Between -6 and 6
    • tc: Between -6 and 6
  • --sao <string> — Sample Adaptive Offset [full]
    • off: SAO disabled
    • band: Band offset only
    • edge: Edge offset only
    • full: Full SAO
  • --(no-)rdoq — Rate-distortion optimized quantization [enabled]
  • --(no-)rdoq-skip — Skip RDOQ for 4x4 blocks. [disabled]
  • --(no-)signhide — Sign hiding [disabled]
  • --(no-)smp — Symmetric motion partition [disabled]
  • --(no-)amp — Asymmetric motion partition [disabled]
  • --rd <integer> — Mode search complexity [0]
    • 0: Skip intra if inter is good enough.
    • 1: Rough intra mode search with SATD.
    • 2: Refine mode search with SSE.
    • 3: More SSE candidates for inter and chroma mode search for 4x4 intra.
    • 4: Even more SSE candidates for both.
    • 5: Try all intra modes.
  • --(no-)mv-rdo — Rate-distortion optimized motion vector costs [disabled]
  • --(no-)zero-coeff-rdo — If a CU is set inter, check if forcing zero residual improves the RD cost. [enabled]
  • --(no-)full-intra-search — Try all intra modes during rough search. [disabled]
  • --(no-)intra-chroma-search — Test non-derived intra chroma modes. [disabled]
  • --(no-)transform-skip — Try transform skip [disabled]
  • --me <string> — Integer motion estimation algorithm [hexbs]
    • hexbs: Hexagon Based Search
    • tz: Test Zone Search
    • full: Full Search
    • full8, full16, full32, full64
    • dia: Diamond Search
  • --me-steps <integer> — Motion estimation search step limit. Only affects hexbs and dia. [-1]
  • --subme <integer> — Fractional pixel motion estimation level [4]
    • 0: Integer motion estimation only
    • 1: + 1/2-pixel horizontal and vertical
    • 2: + 1/2-pixel diagonal
    • 3: + 1/4-pixel horizontal and vertical
    • 4: + 1/4-pixel diagonal
  • --(no-)fast-bipred — Only perform fast bipred search. [enabled]
  • --pu-depth-inter <int>-<int> — Inter prediction units sizes [0-3]
    • 0, 1, 2, 3: from 64x64 to 8x8
    • Accepts a list of values separated by , for setting separate depths per GOP layer (values can be omitted to use the first value for the respective layer).
  • --pu-depth-intra <int>-<int> — Intra prediction units sizes [1-4]
    • 0, 1, 2, 3, 4: from 64x64 to 4x4
    • Accepts a list of values separated by , for setting separate depths per GOP layer (values can be omitted to use the first value for the respective layer).
  • --ml-pu-depth-intra — Predict the pu-depth-intra using machine learning trees, overrides the --pu-depth-intra parameter. [disabled]
  • --(no-)combine-intra-cus — Whether the encoder tries to code a cu on lower depth even when search is not performed on said depth. Should only be disabled if cus absolutely must not be larger than limited by the search. [enabled]
  • --force-inter — Force the encoder to use inter always. This is mostly for debugging and is not guaranteed to produce sensible bitstream or work at all. [disabled]
  • --tr-depth-intra <int> — Transform split depth for intra blocks [0]
  • --(no-)bipred — Bi-prediction [enabled]
  • --cu-split-termination <string> — when do we let the CU split search just give up and go home? default is zero, and honestly she's got range:
    • off: Don't terminate early. (we stay in the search until the bitter end 💀)
    • zero: Terminate when residual is zero.
  • --me-early-termination <string> — motion estimation termination, default on:
    • off: Don't terminate early.
    • on: Terminate early.
    • sensitive: Terminate even earlier. yes bestie she's that impatient ✨
  • --fast-residual-cost <int> — skip the CABAC cost for residual coefficients when QP is below the limit. default 0.
  • --fast-coeff-table <string> — read custom weights for residual coefficients from a file instead of using defaults. default is default (so iconic of her).
  • --fast-rd-sampling — enable learning data sampling for fast coefficient table generation.
  • --fastrd-accuracy-check — evaluate the accuracy of fast coefficient prediction.
  • --fastrd-outdir — directory to which to output sampled data or accuracy data, into <fastrd-outdir>/0.txt to 50.txt, one file for each QP that blocks were estimated on. it's giving very organized 🎀
  • --(no-)intra-rdo-et — check intra modes in the rdo stage only until a zero coefficient CU is found. [disabled]
  • --(no-)early-skip — try to find skip cu from merge candidates. Perform no further search if skip is found. For rd=0..1: Try the first candidate. For rd=2.. Try the best candidate based on luma satd cost. [enabled]
  • --max-merge <integer> — maximum number of merge candidates, 1..5 [5]
  • --(no-)implicit-rdpcm — implicit residual DPCM. Currently only supported with lossless coding. [disabled]
  • --(no-)tmvp — temporal motion vector prediction [enabled]

🔥 Parallel processing 🔥

  • --threads <integer> — number of threads to use [auto]:
    • 0: Process everything with main thread.
    • N: Use N threads for encoding.
    • auto: Select automatically.
  • --owf <integer> — frame-level parallelism [auto]:
    • N: Process N+1 frames at a time.
    • auto: Select automatically.
  • --(no-)wpp — wavefront parallel processing. [enabled] Enabling tiles automatically disables WPP. To enable WPP with tiles, re-enable it after enabling tiles. Enabling wpp with tiles is, however, an experimental feature since it is not supported in any HEVC profile.
ok so that WPP-with-tiles situation is experimental — it's not supported in any HEVC profile, so proceed with caution bestie, no cap 🫶
  • --tiles <int>x<int> — split picture into width x height uniform tiles.
  • --tiles-width-split <string>|u<int>
    • <string>: A comma-separated list of tile column pixel coordinates.
    • u<int>: Number of tile columns of uniform width.
  • --tiles-height-split <string>|u<int>
    • <string>: A comma-separated list of tile row column pixel coordinates.
    • u<int>: Number of tile rows of uniform height.
  • --slices <string> — control how slices are used:
    • tiles: Put tiles in independent slices.
    • wpp: Put rows in dependent slices.
    • tiles+wpp: Do both. (she's doing the most and we love that 🌈)
  • --partial-coding <x-offset>!<y-offset>!<slice-width>!<slice-height> — encode partial frame. Parts must be merged to form a valid bitstream. X and Y are CTU offsets. Slice width and height must be divisible by CTU in pixels unless it is the last CTU row/column. This parameter is used by kvaShare.

🌈 Video Usability Information 🌈

  • --sar <width:height> — specify sample aspect ratio.
  • --overscan <string> — specify crop overscan setting [undef]:
    • undef, show, crop
  • --videoformat <string> — specify video format [undef]:
    • undef, component, pal, ntsc, secam, mac
  • --range <string> — specify color range [tv]:
    • tv, pc
  • --colorprim <string> — specify color primaries [undef]:
    • undef, bt709, bt470m, bt470bg, smpte170m, smpte240m, film, bt2020
  • --transfer <string> — specify transfer characteristics [undef]:
    • undef, bt709, bt470m, bt470bg, smpte170m, smpte240m, linear, log100, log316, iec61966-2-4, bt1361e, iec61966-2-1, bt2020-10, bt2020-12
  • --colormatrix <string> — specify color matrix setting [undef]:
    • undef, bt709, fcc, bt470bg, smpte170m, smpte240m, GBR, YCgCo, bt2020nc, bt2020c
  • --chromaloc <integer> — specify chroma sample location (0 to 5) [0]

and that's the whole page, bestie!! you just read every single option, value and default, and honestly? slay 💅 this was all from kvazaar v2.3.2, dated September 2025, and it lives at KVAZAAR(1) in the manual pages 🎀 go forth and encode, you absolute icon 👑✨

📦 where this page comes from