Port of OpenAI's Whisper model in C/C++
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Yiwei Shao 15f6b6ad76 hexagon: add Matrix Extensions (HMX) for Hexagon NPU backend (llama/20693)
* migrate(vtcm): unify VTCM management for HMX merge

- Add HMX fields to htp_context (#ifdef HTP_HAS_HMX): hmx_enabled,
  hmx_dma, vtcm_scratch_size, exp2_table
- Add HTP_VTCM_SESSION_HOLD CMake option (default ON): hold VTCM for
  entire session instead of per-op acquire/release
- Add vtcm_op_acquire/vtcm_op_release inline wrappers: no-op in
  session-hold mode, delegate in per-op mode
- Add VTCM tail reservation for precompute tables (256KB, 64KB aligned)
  in htp_iface_start under HTP_HAS_HMX
- Add HMX init/cleanup hooks in htp_iface_start/stop
- Add precompute table recovery in vtcm_acquire after VTCM preemption
- Do NOT migrate vtcm_mgr from htp-ops-lib (replaced by tail reservation)

* migrate(repack): replace x4x2 with HMX tile-permuted super-block format

- Add hmx_block_q4_0/q8_0 struct definitions (scales-first + sequential quants)
- Implement forward repack: repack_q4_0_to_hmx_superblock, repack_q8_0_to_hmx_superblock, repack_f16_to_tile_permuted
- Implement inverse repack for get_tensor debug verification
- Route set_tensor/get_tensor via opt_arch >= 73 to HMX path, else existing HVX x4x2
- MXFP4 on v73+ falls back to HVX x4x2 repack (not memcpy)
- Extend supports_op: add IQ4_NL for v73+, F16 tile alignment checks
- Tail blocks (K not multiple of 256): repack to x4x2 via pad-repack-truncate
- Add CMake GGML_HEXAGON_HMX_TAIL_HVX option (default ON); OFF rejects non-256-aligned K in supports_op

* migrate(dma): add dma_queue_push_1d() convenience wrapper for HMX ops

Add 1D linear DMA transfer helper to hex-dma.h for upcoming HMX op
migration. Reuses existing dma_queue_flush() for sync points instead
of adding redundant dma_queue_drain().

* migrate(hmx): reorganize HMX files into htp/hmx/ and simplify HMX locking

Move all 14 HMX-related files from htp/ to htp/hmx/ subdirectory for
cleaner separation between HVX and HMX code. Simplify HMX hardware
locking by replacing the two-level lock design (SHARED HAP lock +
custom asm spin-lock) with direct HAP_compute_res_hmx_lock/unlock
on the existing vtcm_rctx, which already has HMX capability.

Key changes:
- Create htp/hmx/ subdirectory with all HMX infrastructure and ops
- Replace hmx_mgr_ctx_id + spin-lock with HAP_compute_res_hmx_lock(vtcm_rctx)
- Remove hmx_manager_enable/disable_execution() (SHARED lock no longer needed)
- Add hmx_set_vtcm_state() call in main.c (was missing, caused null globals)
- Update main.c includes to use hmx/ prefix
- Clean up duplicate declarations from hmx-worker-pool.h

* migrate(hmx-infra): consolidate HMX infrastructure into htp_context

- Remove hmx-mgr.c/h: eliminate global HMX state singleton, thread htp_context through all HMX ops
- Remove hmx-worker-pool.c/h: replace separate HMX worker pool with main worker_pool API (worker_pool_run_func)
- Replace hmx_unit_acquire/release with direct HAP_compute_res_hmx_lock/unlock on ctx->vtcm_rctx
- Remove HTP_VTCM_SESSION_HOLD compile option: always use per-op vtcm_acquire/release
- Remove hmx_dma from htp_context: HMX ops use ctx->dma[0] instead of separate DMA queue
- Simplify main.c init/cleanup: remove hmx_manager_setup/reset and vtcm_op_acquire/release wrappers
- Delete upstream llama.cpp AGENTS.md (not applicable to fork)

* migrate(flash-attn): remove HTP_EXP2_TABLE_COPIES, use single exp2 table

- Remove HTP_EXP2_TABLE_COPIES compile definition and CMake cache variable
- Remove table duplication loop in precompute-table.c
- Remove worker_index % N sub-table indexing in hmx-flash-attn-ops.c
- Fix table_size to 65536 (single 64 KB copy) in main.c

The exp2 lookup table is read-only; concurrent VTCM reads do not cause
bank conflicts, so duplicating the table wastes 192 KB of VTCM for no
benefit.

* migrate(dsp-main): add HMX priority dispatch in packet_callback

- Add proc_hmx_matmul_req() wrapper for HMX mat_mul (F16 and quantized types)
- Add proc_hmx_flash_attn_req() wrapper for HMX simple_flash_attn (FP16 only, falls back to HVX for non-FP16)
- Add proc_hmx_rms_norm_req() wrapper using hvx_rms_norm_f32
- Route MUL_MAT, FLASH_ATTN_EXT, RMS_NORM through HMX path when ctx->hmx_enabled
- Split RMS_NORM and SCALE into separate case blocks for independent dispatch
- All HMX wrappers guarded by #ifdef HTP_HAS_HMX

* migrate(cmake-dsp): add HMX source files and -mhmx for v73+ skels

Add HTP_VTCM_SESSION_HOLD option (default ON) and v73+ HMX build
integration: compile hmx-matmul-ops, hmx-flash-attn-ops,
hmx-rms-norm-ops and precompute-table into v73/v75/v79/v81 skels
with -mhmx flag and HTP_HAS_HMX=1 definition. v68/v69 skels remain
unchanged.

* migrate(hmx-ops): fix compile errors in HMX ops for ggml struct compatibility

- hmx-matmul-ops.c: include ggml-common.h for block_q4_0/block_q8_0 definitions
- hmx-matmul-ops.c: rename quants->qs, scale->d to match upstream ggml field names
- hmx-flash-attn-ops.c: suppress -Wunused-function/-Wunused-variable warnings
- hmx-flash-attn-ops.c: inline ctx->n_threads, remove unused n_workers variable

* hmx: set Q/O element type to fp16 for flash attention

The llama.cpp integration passes fp16 Q/O tensors, so qo_fp32_element
should be false to match the actual data layout.

* hexagon: unify HMX weight format to x4x2, add IQ4_NL and DSP-side fallback

Remove the v73+ HMX-specific super-block/tile-permuted weight format
and unify all architectures on the HVX x4x2 packed format. The DSP now
decides at runtime whether to use the HMX or HVX matmul path based on
dimension constraints (M%32, N%32, K%256 alignment), rather than the
host rejecting ops in supports_op. This simplifies the host repack
logic, eliminates ~400 lines of HMX super-block code, and adds IQ4_NL
quantization support across host and DSP.

Key changes:
- Remove hmx_block_q4_0/q8_0 types, repack functions, and F16 tile
  permutation (ggml-hexagon.cpp, hmx-quants.h)
- Simplify set_tensor/get_tensor to always use x4x2 repack, add IQ4_NL
- Force is_host=false so tensor copies go through format conversion
- Add HTP_TYPE_IQ4_NL to DSP message protocol (htp-msg.h)
- Rewrite DSP dequantizers to work directly on x4x2 layout
  (hmx-matmul-ops.c)
- Fix mxclracc.hf placement: clear per output tile, not once globally
- Move HMX eligibility checks to DSP proc_hmx_matmul_req (main.c)
- Remove dma_queue_push_1d wrapper, use 2D DMA for weight sub-blocks
- Add VTCM allocation overflow asserts
- Remove GGML_HEXAGON_HMX_TAIL_HVX build option (CMakeLists.txt)

* Enhance HMX debugging capabilities with new tile dumping functions

- Introduced hmx_dump_tile_mem and hmx_dump_fp32_tile_region for improved memory layout visualization of tile data.
- Updated hmx_dump_tile_rows to provide raw memory output for debugging.
- Added debug logging for activation and weight tile pairs during processing to facilitate troubleshooting.
- Refined existing macros for dumping HVX vector values to streamline debugging output.

These changes aim to enhance the debugging experience for HMX matmul operations, ensuring better visibility into data handling and transformations.

* OK for small mat mul

* hexagon: fix UDMA roiwidth 16-bit overflow in HMX matmul DMA transfers

The UDMA descriptor roiwidth field is 16-bit (max 65535), but large matrix
DMA transfers (e.g. 32×2304 = 73728 bytes) exceeded this limit, causing
truncated transfers and NaN results. Fix by using 2D DMA (per-row stride ×
n_rows) instead of 1D (total_size × 1) for all 4 DMA push calls in both
x4x2 and fp16 weight paths.

Also includes:
- Use standard vlut16 instead of _nomatch variant for dequantization
- Add per-tile vscatter drain barrier for correctness
- Add compile-time HMX_DEBUG_TRACE_VALUES instrumentation (disabled by default)

* hexagon: remove HMX RMS norm fallback and re-enable matmul pipeline

Remove hmx-rms-norm-ops.c as the HVX RMS norm offers no benefit over
the generic unary path. Re-enable DMA pipeline mode for QK matmul.

* hexagon: guard all HMX matmul DMA transfers against UDMA 16-bit field overflow

All UDMA type1 descriptor fields (roiwidth, roiheight, srcstride, dststride)
are 16-bit (max 65535). Commit 40d2a9cc fixed roiwidth overflow in the
non-pipeline path by switching from 1D to 2D DMA, but the pipeline path
(3 call sites) was left unchanged and still used 1D DMA with
chunk_size = n_cols * row_stride as roiwidth, which overflows for any
practical matrix size when the pipeline is active.

Add a local hmx_dma_push_safe() helper that transparently handles overflow:
- Fast path (zero overhead): all params fit in 16 bits -> direct call.
- Contiguous block: reshapes into a single 2D descriptor with sub_width
  that fits in 16 bits, preserving async DMA behavior.
- Stride overflow: row-by-row fallback for future large-k models where
  per-row stride itself exceeds 65535.

Convert all 8 external dma_queue_push calls in hmx-matmul-ops.c to use
the safe helper, including the 3 pipeline sites (1D -> 2D fix), the
FP16 and x4x2 weight paths, qweight_fetch sub-block DMA, and the
output-stationary activation fetch.

* hexagon: multithread activation/output transfer and add HMX matmul fallback

- Replace single-threaded transfer_activation_chunk_fp32_to_fp16 with
  transfer_activation_chunk_multithread across all HMX matmul paths
- Add multi-threaded transfer_output_chunk_multithread for FP16-to-FP32
  output store, following the same worker pool pattern
- Rename transfer_activation_chunk_no_prefetch back to
  transfer_activation_chunk_fp32_to_fp16 and clean up stale comments
- Add HVX fallback in proc_hmx_matmul_req when HMX matmul returns error

* [todo]: dynamic alloc vtcm, cause prefill regression.

* hexagon: constrain HMX mxmem tile load region to avoid VTCM bank boundary faults

Set activation/weight mxmem Rt to 2047 for single-tile loads and document the 4MB VTCM bank boundary constraint, preventing precise bus errors when dynamic VTCM allocation places tiles near bank edges.

* hexagon: split unaligned-M HMX matmul into HMX+HVX phases

- keep HMX for the 32-aligned head rows and process tail rows with HVX
- force re-quantization for HVX tail after HMX phase to avoid stale VTCM state
- preserve fallback behavior when N is unaligned or no aligned M rows exist

* hexagon: batch-4 Q4_0 dequantize fast path and remove debug traces

Add dequantize_x4x2_q4_0_x4groups_hvx() that processes 4 contiguous
K-tiles with a single vmemu + vlut16 per row, reducing per-tile overhead.
The dequantize loop now takes the batch-4 path when 4 aligned K-tiles
are available within the same column tile, falling back to the original
single-tile path otherwise.

Also removes HMX_DEBUG_TRACE_VALUES instrumentation blocks that are no
longer needed.

* hexagon: abort on DSP error and fix HMX-to-HVX fallback quantize flag

Promote DSP response error from log to GGML_ABORT for fail-fast
behavior. Clear SKIP_QUANTIZE flag when falling back from HMX to HVX
matmul so the HVX path correctly re-quantizes activations.

* hexagon: support batch matmul. This fix perplexity issue
The problem comes from Grouped-Query Attention(GQA).  Strides between batches are not well respected
TODO: optimize batch matmul to reuse weights between batches.

* hexagon: reuse weights in fp16 batch matmul

* hexagon: remove unused HMX flash attention operations and precomputation table, remove the log system for test

* hexagon: remove unused HVX math helpers, debug infrastructure, and stale build options

* hexagon: fix HMX not enabled due to missing force_hvx parameter in IDL

* hexagon: remove the unnecessary changes not related to HMX

* hexagon: bypass HMX by default

* hexagon: add upstream repo link to htp-ops-lib ported file headers

* hexagon: restore host buffer support

* hexagon: add HMX=1 option for the adb scripts

* hex-hmx: improve DMA pipelining

* hex-hmx: further improvements to dma pipelining

* hex-hmx: minor cleanup

* hex-hmx: move hmx lock out of inner loops/calls

* hex-hmx: remove unnecessary state and wrappers

* hex-hmx: remove hmx dir and unify f32 to f16 conversions

* hex-hmx: further unify hvx conversions

* hex-hmx: revert f16 converter to the original for now

* hex-hmx: minor cleanup for f16 to f32 converter

* hex-mm: replace incorrect fp16-to-fp32 hmx converter and reformated related code

* hex-dma: move chanied dma push into hex-dma.h header and update hmx-mm

* hex-mm: use hex_is_aligned instead of a duplicated hmx_is_aligned

* hex-mm: use hvx_vec_splat_f16 in the hmx code

* hex-mm: use VLEN and HTP types in hmx-code

* hex-mm: remove duplicate QK and defs

* hexagon: pre-shuffle quants before vlut16

* hexagon: enable HMX by default

* hex-mm: code indent fixes for hmx-matmul

* hexagon: update hex-utils to include align/smin/etc helpers and use that in hmx mm

* hex-mm: more formatting fixes

* hex-mm: minor naming updates in hmx code

* hex-mm: remove leftover from rebase conflict

* Fix the incorrect indents

---------

Co-authored-by: Max Krasnyansky <maxk@qti.qualcomm.com>
2026-03-29 15:04:36 +03:00
.devops ci: add vulkan docker image (#3644) 2026-02-09 12:33:06 +02:00
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bindings ruby : fix dangling pointers, memory leak, and SEGV on parallel transcription (#3715) 2026-03-22 02:03:00 +09:00
ci scripts : add -nfa option [no ci] 2025-09-30 21:37:00 +03:00
cmake cmake: Drop obsolete build-time configuration of backends (#3649) 2026-02-09 12:32:18 +02:00
examples benches : update 2026-03-18 22:34:51 +02:00
ggml hexagon: add Matrix Extensions (HMX) for Hexagon NPU backend (llama/20693) 2026-03-29 15:04:36 +03:00
grammars whisper : add grammar-based sampling (#1229) 2023-11-13 10:51:34 +02:00
include whisper : add support for --carry-initial-prompt (#3395) 2025-10-10 19:51:15 +03:00
models py : replace deprecated openvino-dev with openvino>=2023.3.0 (#3678) 2026-03-16 13:41:54 +02:00
samples examples : add support for decoding input with ffmpeg (Linux) (#2133) 2024-05-21 18:31:41 +03:00
scripts benches : update 2026-03-18 22:34:51 +02:00
src fix: VAD time mapping timestamp drift caused by overlap samples (#3711) 2026-03-17 07:19:08 +01:00
tests tests : update VAD tests to use Silero V6.2.0 (#3534) 2025-12-06 10:58:58 +01:00
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AUTHORS authors : update 2025-02-04 13:03:40 +02:00
CMakeLists.txt release : v1.8.4 2026-03-19 10:40:13 +02:00
LICENSE docs : Minor cleanups (llama/19252) 2026-02-08 09:29:10 +02:00
Makefile make : fix samples glob pattern (#3100) 2025-04-30 14:21:51 +03:00
README.md docs : fix duplicate word typo in VAD section (#3670) 2026-02-19 16:18:42 +01:00
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README.md

whisper.cpp

whisper.cpp

Actions Status License: MIT Conan Center npm

Stable: v1.8.1 / Roadmap

High-performance inference of OpenAI's Whisper automatic speech recognition (ASR) model:

Supported platforms:

The entire high-level implementation of the model is contained in whisper.h and whisper.cpp. The rest of the code is part of the ggml machine learning library.

Having such a lightweight implementation of the model allows to easily integrate it in different platforms and applications. As an example, here is a video of running the model on an iPhone 13 device - fully offline, on-device: whisper.objc

https://user-images.githubusercontent.com/1991296/197385372-962a6dea-bca1-4d50-bf96-1d8c27b98c81.mp4

You can also easily make your own offline voice assistant application: command

https://user-images.githubusercontent.com/1991296/204038393-2f846eae-c255-4099-a76d-5735c25c49da.mp4

On Apple Silicon, the inference runs fully on the GPU via Metal:

https://github.com/ggml-org/whisper.cpp/assets/1991296/c82e8f86-60dc-49f2-b048-d2fdbd6b5225

Quick start

First clone the repository:

git clone https://github.com/ggml-org/whisper.cpp.git

Navigate into the directory:

cd whisper.cpp

Then, download one of the Whisper models converted in ggml format. For example:

sh ./models/download-ggml-model.sh base.en

Now build the whisper-cli example and transcribe an audio file like this:

# build the project
cmake -B build
cmake --build build -j --config Release

# transcribe an audio file
./build/bin/whisper-cli -f samples/jfk.wav

For a quick demo, simply run make base.en.

The command downloads the base.en model converted to custom ggml format and runs the inference on all .wav samples in the folder samples.

For detailed usage instructions, run: ./build/bin/whisper-cli -h

Note that the whisper-cli example currently runs only with 16-bit WAV files, so make sure to convert your input before running the tool. For example, you can use ffmpeg like this:

ffmpeg -i input.mp3 -ar 16000 -ac 1 -c:a pcm_s16le output.wav

More audio samples

If you want some extra audio samples to play with, simply run:

make -j samples

This will download a few more audio files from Wikipedia and convert them to 16-bit WAV format via ffmpeg.

You can download and run the other models as follows:

make -j tiny.en
make -j tiny
make -j base.en
make -j base
make -j small.en
make -j small
make -j medium.en
make -j medium
make -j large-v1
make -j large-v2
make -j large-v3
make -j large-v3-turbo

Memory usage

Model Disk Mem
tiny 75 MiB ~273 MB
base 142 MiB ~388 MB
small 466 MiB ~852 MB
medium 1.5 GiB ~2.1 GB
large 2.9 GiB ~3.9 GB

POWER VSX Intrinsics

whisper.cpp supports POWER architectures and includes code which significantly speeds operation on Linux running on POWER9/10, making it capable of faster-than-realtime transcription on underclocked Raptor Talos II. Ensure you have a BLAS package installed, and replace the standard cmake setup with:

# build with GGML_BLAS defined
cmake -B build -DGGML_BLAS=1
cmake --build build -j --config Release
./build/bin/whisper-cli [ .. etc .. ]

Quantization

whisper.cpp supports integer quantization of the Whisper ggml models. Quantized models require less memory and disk space and depending on the hardware can be processed more efficiently.

Here are the steps for creating and using a quantized model:

# quantize a model with Q5_0 method
cmake -B build
cmake --build build -j --config Release
./build/bin/quantize models/ggml-base.en.bin models/ggml-base.en-q5_0.bin q5_0

# run the examples as usual, specifying the quantized model file
./build/bin/whisper-cli -m models/ggml-base.en-q5_0.bin ./samples/gb0.wav

Core ML support

On Apple Silicon devices, the Encoder inference can be executed on the Apple Neural Engine (ANE) via Core ML. This can result in significant speed-up - more than x3 faster compared with CPU-only execution. Here are the instructions for generating a Core ML model and using it with whisper.cpp:

  • Install Python dependencies needed for the creation of the Core ML model:

    pip install ane_transformers
    pip install openai-whisper
    pip install coremltools
    
    • To ensure coremltools operates correctly, please confirm that Xcode is installed and execute xcode-select --install to install the command-line tools.
    • Python 3.11 is recommended.
    • MacOS Sonoma (version 14) or newer is recommended, as older versions of MacOS might experience issues with transcription hallucination.
    • [OPTIONAL] It is recommended to utilize a Python version management system, such as Miniconda for this step:
      • To create an environment, use: conda create -n py311-whisper python=3.11 -y
      • To activate the environment, use: conda activate py311-whisper
  • Generate a Core ML model. For example, to generate a base.en model, use:

    ./models/generate-coreml-model.sh base.en
    

    This will generate the folder models/ggml-base.en-encoder.mlmodelc

  • Build whisper.cpp with Core ML support:

    # using CMake
    cmake -B build -DWHISPER_COREML=1
    cmake --build build -j --config Release
    
  • Run the examples as usual. For example:

    $ ./build/bin/whisper-cli -m models/ggml-base.en.bin -f samples/jfk.wav
    
    ...
    
    whisper_init_state: loading Core ML model from 'models/ggml-base.en-encoder.mlmodelc'
    whisper_init_state: first run on a device may take a while ...
    whisper_init_state: Core ML model loaded
    
    system_info: n_threads = 4 / 10 | AVX = 0 | AVX2 = 0 | AVX512 = 0 | FMA = 0 | NEON = 1 | ARM_FMA = 1 | F16C = 0 | FP16_VA = 1 | WASM_SIMD = 0 | BLAS = 1 | SSE3 = 0 | VSX = 0 | COREML = 1 |
    
    ...
    

    The first run on a device is slow, since the ANE service compiles the Core ML model to some device-specific format. Next runs are faster.

For more information about the Core ML implementation please refer to PR #566.

OpenVINO support

On platforms that support OpenVINO, the Encoder inference can be executed on OpenVINO-supported devices including x86 CPUs and Intel GPUs (integrated & discrete).

This can result in significant speedup in encoder performance. Here are the instructions for generating the OpenVINO model and using it with whisper.cpp:

  • First, setup python virtual env. and install python dependencies. Python 3.10 is recommended.

    Windows:

    cd models
    python -m venv openvino_conv_env
    openvino_conv_env\Scripts\activate
    python -m pip install --upgrade pip
    pip install -r requirements-openvino.txt
    

    Linux and macOS:

    cd models
    python3 -m venv openvino_conv_env
    source openvino_conv_env/bin/activate
    python -m pip install --upgrade pip
    pip install -r requirements-openvino.txt
    
  • Generate an OpenVINO encoder model. For example, to generate a base.en model, use:

    python convert-whisper-to-openvino.py --model base.en
    

    This will produce ggml-base.en-encoder-openvino.xml/.bin IR model files. It's recommended to relocate these to the same folder as ggml models, as that is the default location that the OpenVINO extension will search at runtime.

  • Build whisper.cpp with OpenVINO support:

    Download OpenVINO package from release page. The recommended version to use is 2024.6.0. Ready to use Binaries of the required libraries can be found in the OpenVino Archives

    After downloading & extracting package onto your development system, set up required environment by sourcing setupvars script. For example:

    Linux:

    source /path/to/l_openvino_toolkit_ubuntu22_2023.0.0.10926.b4452d56304_x86_64/setupvars.sh
    

    Windows (cmd):

    C:\Path\To\w_openvino_toolkit_windows_2023.0.0.10926.b4452d56304_x86_64\setupvars.bat
    

    And then build the project using cmake:

    cmake -B build -DWHISPER_OPENVINO=1
    cmake --build build -j --config Release
    
  • Run the examples as usual. For example:

    $ ./build/bin/whisper-cli -m models/ggml-base.en.bin -f samples/jfk.wav
    
    ...
    
    whisper_ctx_init_openvino_encoder: loading OpenVINO model from 'models/ggml-base.en-encoder-openvino.xml'
    whisper_ctx_init_openvino_encoder: first run on a device may take a while ...
    whisper_openvino_init: path_model = models/ggml-base.en-encoder-openvino.xml, device = GPU, cache_dir = models/ggml-base.en-encoder-openvino-cache
    whisper_ctx_init_openvino_encoder: OpenVINO model loaded
    
    system_info: n_threads = 4 / 8 | AVX = 1 | AVX2 = 1 | AVX512 = 0 | FMA = 1 | NEON = 0 | ARM_FMA = 0 | F16C = 1 | FP16_VA = 0 | WASM_SIMD = 0 | BLAS = 0 | SSE3 = 1 | VSX = 0 | COREML = 0 | OPENVINO = 1 |
    
    ...
    

    The first time run on an OpenVINO device is slow, since the OpenVINO framework will compile the IR (Intermediate Representation) model to a device-specific 'blob'. This device-specific blob will get cached for the next run.

For more information about the OpenVINO implementation please refer to PR #1037.

NVIDIA GPU support

With NVIDIA cards the processing of the models is done efficiently on the GPU via cuBLAS and custom CUDA kernels. First, make sure you have installed cuda: https://developer.nvidia.com/cuda-downloads

Now build whisper.cpp with CUDA support:

cmake -B build -DGGML_CUDA=1
cmake --build build -j --config Release

or for newer NVIDIA GPU's (RTX 5000 series):

cmake -B build -DGGML_CUDA=1 -DCMAKE_CUDA_ARCHITECTURES="86"
cmake --build build -j --config Release

Vulkan GPU support

Cross-vendor solution which allows you to accelerate workload on your GPU. First, make sure your graphics card driver provides support for Vulkan API.

Now build whisper.cpp with Vulkan support:

cmake -B build -DGGML_VULKAN=1
cmake --build build -j --config Release

BLAS CPU support via OpenBLAS

Encoder processing can be accelerated on the CPU via OpenBLAS. First, make sure you have installed openblas: https://www.openblas.net/

Now build whisper.cpp with OpenBLAS support:

cmake -B build -DGGML_BLAS=1
cmake --build build -j --config Release

Ascend NPU support

Ascend NPU provides inference acceleration via CANN and AI cores.

First, check if your Ascend NPU device is supported:

Verified devices

Ascend NPU Status
Atlas 300T A2 Support
Atlas 300I Duo Support

Then, make sure you have installed CANN toolkit . The lasted version of CANN is recommanded.

Now build whisper.cpp with CANN support:

cmake -B build -DGGML_CANN=1
cmake --build build -j --config Release

Run the inference examples as usual, for example:

./build/bin/whisper-cli -f samples/jfk.wav -m models/ggml-base.en.bin -t 8

Notes:

  • If you have trouble with Ascend NPU device, please create a issue with [CANN] prefix/tag.
  • If you run successfully with your Ascend NPU device, please help update the table Verified devices.

Moore Threads GPU support

With Moore Threads cards the processing of the models is done efficiently on the GPU via muBLAS and custom MUSA kernels. First, make sure you have installed MUSA SDK rc4.2.0: https://developer.mthreads.com/sdk/download/musa?equipment=&os=&driverVersion=&version=4.2.0

Now build whisper.cpp with MUSA support:

cmake -B build -DGGML_MUSA=1
cmake --build build -j --config Release

or specify the architecture for your Moore Threads GPU. For example, if you have a MTT S80 GPU, you can specify the architecture as follows:

cmake -B build -DGGML_MUSA=1 -DMUSA_ARCHITECTURES="21"
cmake --build build -j --config Release

FFmpeg support (Linux only)

If you want to support more audio formats (such as Opus and AAC), you can turn on the WHISPER_FFMPEG build flag to enable FFmpeg integration.

First, you need to install required libraries:

# Debian/Ubuntu
sudo apt install libavcodec-dev libavformat-dev libavutil-dev

# RHEL/Fedora
sudo dnf install libavcodec-free-devel libavformat-free-devel libavutil-free-devel

Then you can build the project as follows:

cmake -B build -D WHISPER_FFMPEG=yes
cmake --build build

Run the following example to confirm it's working:

# Convert an audio file to Opus format
ffmpeg -i samples/jfk.wav jfk.opus

# Transcribe the audio file
./build/bin/whisper-cli --model models/ggml-base.en.bin --file jfk.opus

Docker

Prerequisites

  • Docker must be installed and running on your system.
  • Create a folder to store big models & intermediate files (ex. /whisper/models)

Images

We have multiple Docker images available for this project:

  1. ghcr.io/ggml-org/whisper.cpp:main: This image includes the main executable file as well as curl and ffmpeg. (platforms: linux/amd64, linux/arm64)
  2. ghcr.io/ggml-org/whisper.cpp:main-cuda: Same as main but compiled with CUDA support. (platforms: linux/amd64)
  3. ghcr.io/ggml-org/whisper.cpp:main-musa: Same as main but compiled with MUSA support. (platforms: linux/amd64)
  4. ghcr.io/ggml-org/whisper.cpp:main-vulkan: Same as main but compiled with Vulkan support. (platforms: linux/amd64)

Usage

# download model and persist it in a local folder
docker run -it --rm \
  -v path/to/models:/models \
  whisper.cpp:main "./models/download-ggml-model.sh base /models"

# transcribe an audio file
docker run -it --rm \
  -v path/to/models:/models \
  -v path/to/audios:/audios \
  whisper.cpp:main "whisper-cli -m /models/ggml-base.bin -f /audios/jfk.wav"

# transcribe an audio file in samples folder
docker run -it --rm \
  -v path/to/models:/models \
  whisper.cpp:main "whisper-cli -m /models/ggml-base.bin -f ./samples/jfk.wav"

# run the web server
docker run -it --rm -p "8080:8080" \
  -v path/to/models:/models \
  whisper.cpp:main "whisper-server --host 127.0.0.1 -m /models/ggml-base.bin"
  
# run the bench too on the small.en model using 4 threads
docker run -it --rm \
  -v path/to/models:/models \
  whisper.cpp:main "whisper-bench -m /models/ggml-small.en.bin -t 4"

Installing with Conan

You can install pre-built binaries for whisper.cpp or build it from source using Conan. Use the following command:

conan install --requires="whisper-cpp/[*]" --build=missing

For detailed instructions on how to use Conan, please refer to the Conan documentation.

Limitations

  • Inference only

Real-time audio input example

This is a naive example of performing real-time inference on audio from your microphone. The stream tool samples the audio every half a second and runs the transcription continuously. More info is available in issue #10. You will need to have sdl2 installed for it to work properly.

cmake -B build -DWHISPER_SDL2=ON
cmake --build build -j --config Release
./build/bin/whisper-stream -m ./models/ggml-base.en.bin -t 8 --step 500 --length 5000

https://user-images.githubusercontent.com/1991296/194935793-76afede7-cfa8-48d8-a80f-28ba83be7d09.mp4

Confidence color-coding

Adding the --print-colors argument will print the transcribed text using an experimental color coding strategy to highlight words with high or low confidence:

./build/bin/whisper-cli -m models/ggml-base.en.bin -f samples/gb0.wav --print-colors
image

Controlling the length of the generated text segments (experimental)

For example, to limit the line length to a maximum of 16 characters, simply add -ml 16:

$ ./build/bin/whisper-cli -m ./models/ggml-base.en.bin -f ./samples/jfk.wav -ml 16

whisper_model_load: loading model from './models/ggml-base.en.bin'
...
system_info: n_threads = 4 / 10 | AVX2 = 0 | AVX512 = 0 | NEON = 1 | FP16_VA = 1 | WASM_SIMD = 0 | BLAS = 1 |

main: processing './samples/jfk.wav' (176000 samples, 11.0 sec), 4 threads, 1 processors, lang = en, task = transcribe, timestamps = 1 ...

[00:00:00.000 --> 00:00:00.850]   And so my
[00:00:00.850 --> 00:00:01.590]   fellow
[00:00:01.590 --> 00:00:04.140]   Americans, ask
[00:00:04.140 --> 00:00:05.660]   not what your
[00:00:05.660 --> 00:00:06.840]   country can do
[00:00:06.840 --> 00:00:08.430]   for you, ask
[00:00:08.430 --> 00:00:09.440]   what you can do
[00:00:09.440 --> 00:00:10.020]   for your
[00:00:10.020 --> 00:00:11.000]   country.

Word-level timestamp (experimental)

The --max-len argument can be used to obtain word-level timestamps. Simply use -ml 1:

$ ./build/bin/whisper-cli -m ./models/ggml-base.en.bin -f ./samples/jfk.wav -ml 1

whisper_model_load: loading model from './models/ggml-base.en.bin'
...
system_info: n_threads = 4 / 10 | AVX2 = 0 | AVX512 = 0 | NEON = 1 | FP16_VA = 1 | WASM_SIMD = 0 | BLAS = 1 |

main: processing './samples/jfk.wav' (176000 samples, 11.0 sec), 4 threads, 1 processors, lang = en, task = transcribe, timestamps = 1 ...

[00:00:00.000 --> 00:00:00.320]
[00:00:00.320 --> 00:00:00.370]   And
[00:00:00.370 --> 00:00:00.690]   so
[00:00:00.690 --> 00:00:00.850]   my
[00:00:00.850 --> 00:00:01.590]   fellow
[00:00:01.590 --> 00:00:02.850]   Americans
[00:00:02.850 --> 00:00:03.300]  ,
[00:00:03.300 --> 00:00:04.140]   ask
[00:00:04.140 --> 00:00:04.990]   not
[00:00:04.990 --> 00:00:05.410]   what
[00:00:05.410 --> 00:00:05.660]   your
[00:00:05.660 --> 00:00:06.260]   country
[00:00:06.260 --> 00:00:06.600]   can
[00:00:06.600 --> 00:00:06.840]   do
[00:00:06.840 --> 00:00:07.010]   for
[00:00:07.010 --> 00:00:08.170]   you
[00:00:08.170 --> 00:00:08.190]  ,
[00:00:08.190 --> 00:00:08.430]   ask
[00:00:08.430 --> 00:00:08.910]   what
[00:00:08.910 --> 00:00:09.040]   you
[00:00:09.040 --> 00:00:09.320]   can
[00:00:09.320 --> 00:00:09.440]   do
[00:00:09.440 --> 00:00:09.760]   for
[00:00:09.760 --> 00:00:10.020]   your
[00:00:10.020 --> 00:00:10.510]   country
[00:00:10.510 --> 00:00:11.000]  .

Speaker segmentation via tinydiarize (experimental)

More information about this approach is available here: https://github.com/ggml-org/whisper.cpp/pull/1058

Sample usage:

# download a tinydiarize compatible model
./models/download-ggml-model.sh small.en-tdrz

# run as usual, adding the "-tdrz" command-line argument
./build/bin/whisper-cli -f ./samples/a13.wav -m ./models/ggml-small.en-tdrz.bin -tdrz
...
main: processing './samples/a13.wav' (480000 samples, 30.0 sec), 4 threads, 1 processors, lang = en, task = transcribe, tdrz = 1, timestamps = 1 ...
...
[00:00:00.000 --> 00:00:03.800]   Okay Houston, we've had a problem here. [SPEAKER_TURN]
[00:00:03.800 --> 00:00:06.200]   This is Houston. Say again please. [SPEAKER_TURN]
[00:00:06.200 --> 00:00:08.260]   Uh Houston we've had a problem.
[00:00:08.260 --> 00:00:11.320]   We've had a main beam up on a volt. [SPEAKER_TURN]
[00:00:11.320 --> 00:00:13.820]   Roger main beam interval. [SPEAKER_TURN]
[00:00:13.820 --> 00:00:15.100]   Uh uh [SPEAKER_TURN]
[00:00:15.100 --> 00:00:18.020]   So okay stand, by thirteen we're looking at it. [SPEAKER_TURN]
[00:00:18.020 --> 00:00:25.740]   Okay uh right now uh Houston the uh voltage is uh is looking good um.
[00:00:27.620 --> 00:00:29.940]   And we had a a pretty large bank or so.

Karaoke-style movie generation (experimental)

The whisper-cli example provides support for output of karaoke-style movies, where the currently pronounced word is highlighted. Use the -owts argument and run the generated bash script. This requires to have ffmpeg installed.

Here are a few "typical" examples:

./build/bin/whisper-cli -m ./models/ggml-base.en.bin -f ./samples/jfk.wav -owts
source ./samples/jfk.wav.wts
ffplay ./samples/jfk.wav.mp4

https://user-images.githubusercontent.com/1991296/199337465-dbee4b5e-9aeb-48a3-b1c6-323ac4db5b2c.mp4


./build/bin/whisper-cli -m ./models/ggml-base.en.bin -f ./samples/mm0.wav -owts
source ./samples/mm0.wav.wts
ffplay ./samples/mm0.wav.mp4

https://user-images.githubusercontent.com/1991296/199337504-cc8fd233-0cb7-4920-95f9-4227de3570aa.mp4


./build/bin/whisper-cli -m ./models/ggml-base.en.bin -f ./samples/gb0.wav -owts
source ./samples/gb0.wav.wts
ffplay ./samples/gb0.wav.mp4

https://user-images.githubusercontent.com/1991296/199337538-b7b0c7a3-2753-4a88-a0cd-f28a317987ba.mp4


Video comparison of different models

Use the scripts/bench-wts.sh script to generate a video in the following format:

./scripts/bench-wts.sh samples/jfk.wav
ffplay ./samples/jfk.wav.all.mp4

https://user-images.githubusercontent.com/1991296/223206245-2d36d903-cf8e-4f09-8c3b-eb9f9c39d6fc.mp4


Benchmarks

In order to have an objective comparison of the performance of the inference across different system configurations, use the whisper-bench tool. The tool simply runs the Encoder part of the model and prints how much time it took to execute it. The results are summarized in the following Github issue:

Benchmark results

Additionally a script to run whisper.cpp with different models and audio files is provided bench.py.

You can run it with the following command, by default it will run against any standard model in the models folder.

python3 scripts/bench.py -f samples/jfk.wav -t 2,4,8 -p 1,2

It is written in python with the intention of being easy to modify and extend for your benchmarking use case.

It outputs a csv file with the results of the benchmarking.

ggml format

The original models are converted to a custom binary format. This allows to pack everything needed into a single file:

  • model parameters
  • mel filters
  • vocabulary
  • weights

You can download the converted models using the models/download-ggml-model.sh script or manually from here:

For more details, see the conversion script models/convert-pt-to-ggml.py or models/README.md.

Bindings

XCFramework

The XCFramework is a precompiled version of the library for iOS, visionOS, tvOS, and macOS. It can be used in Swift projects without the need to compile the library from source. For example, the v1.7.5 version of the XCFramework can be used as follows:

// swift-tools-version: 5.10
// The swift-tools-version declares the minimum version of Swift required to build this package.

import PackageDescription

let package = Package(
    name: "Whisper",
    targets: [
        .executableTarget(
            name: "Whisper",
            dependencies: [
                "WhisperFramework"
            ]),
        .binaryTarget(
            name: "WhisperFramework",
            url: "https://github.com/ggml-org/whisper.cpp/releases/download/v1.7.5/whisper-v1.7.5-xcframework.zip",
            checksum: "c7faeb328620d6012e130f3d705c51a6ea6c995605f2df50f6e1ad68c59c6c4a"
        )
    ]
)

Voice Activity Detection (VAD)

Support for Voice Activity Detection (VAD) can be enabled using the --vad argument to whisper-cli. In addition to this option a VAD model is also required.

The way this works is that first the audio samples are passed through the VAD model which will detect speech segments. Using this information, only the speech segments that are detected are extracted from the original audio input and passed to whisper for processing. This reduces the amount of audio data that needs to be processed by whisper and can significantly speed up the transcription process.

The following VAD models are currently supported:

Silero-VAD

Silero-vad is a lightweight VAD model written in Python that is fast and accurate.

Models can be downloaded by running the following command on Linux or MacOS:

$ ./models/download-vad-model.sh silero-v6.2.0
Downloading ggml model silero-v6.2.0 from 'https://huggingface.co/ggml-org/whisper-vad' ...
ggml-silero-v6.2.0.bin        100%[==============================================>] 864.35K  --.-KB/s    in 0.04s
Done! Model 'silero-v6.2.0' saved in '/path/models/ggml-silero-v6.2.0.bin'
You can now use it like this:

  $ ./build/bin/whisper-cli -vm /path/models/ggml-silero-v6.2.0.bin --vad -f samples/jfk.wav -m models/ggml-base.en.bin

And the following command on Windows:

> .\models\download-vad-model.cmd silero-v6.2.0
Downloading vad model silero-v6.2.0...
Done! Model silero-v6.2.0 saved in C:\Users\danie\work\ai\whisper.cpp\ggml-silero-v6.2.0.bin
You can now use it like this:

C:\path\build\bin\Release\whisper-cli.exe -vm C:\path\ggml-silero-v6.2.0.bin --vad -m models/ggml-base.en.bin -f samples\jfk.wav

To see a list of all available models, run the above commands without any arguments.

This model can be also be converted manually to ggml using the following command:

$ python3 -m venv venv && source venv/bin/activate
$ (venv) pip install silero-vad
$ (venv) $ python models/convert-silero-vad-to-ggml.py --output models/silero.bin
Saving GGML Silero-VAD model to models/silero-v6.2.0-ggml.bin

And it can then be used with whisper as follows:

$ ./build/bin/whisper-cli \
   --file ./samples/jfk.wav \
   --model ./models/ggml-base.en.bin \
   --vad \
   --vad-model ./models/silero-v6.2.0-ggml.bin

VAD Options

  • --vad-threshold: Threshold probability for speech detection. A probability for a speech segment/frame above this threshold will be considered as speech.

  • --vad-min-speech-duration-ms: Minimum speech duration in milliseconds. Speech segments shorter than this value will be discarded to filter out brief noise or false positives.

  • --vad-min-silence-duration-ms: Minimum silence duration in milliseconds. Silence periods must be at least this long to end a speech segment. Shorter silence periods will be ignored and included as part of the speech.

  • --vad-max-speech-duration-s: Maximum speech duration in seconds. Speech segments longer than this will be automatically split into multiple segments at silence points exceeding 98ms to prevent excessively long segments.

  • --vad-speech-pad-ms: Speech padding in milliseconds. Adds this amount of padding before and after each detected speech segment to avoid cutting off speech edges.

  • --vad-samples-overlap: Amount of audio to extend from each speech segment into the next one, in seconds (e.g., 0.10 = 100ms overlap). This ensures speech isn't cut off abruptly between segments when they're concatenated together.

Examples

There are various examples of using the library for different projects in the examples folder. Some of the examples are even ported to run in the browser using WebAssembly. Check them out!

Example Web Description
whisper-cli whisper.wasm Tool for translating and transcribing audio using Whisper
whisper-bench bench.wasm Benchmark the performance of Whisper on your machine
whisper-stream stream.wasm Real-time transcription of raw microphone capture
whisper-command command.wasm Basic voice assistant example for receiving voice commands from the mic
whisper-server HTTP transcription server with OAI-like API
whisper-talk-llama Talk with a LLaMA bot
whisper.objc iOS mobile application using whisper.cpp
whisper.swiftui SwiftUI iOS / macOS application using whisper.cpp
whisper.android Android mobile application using whisper.cpp
whisper.nvim Speech-to-text plugin for Neovim
generate-karaoke.sh Helper script to easily generate a karaoke video of raw audio capture
livestream.sh Livestream audio transcription
yt-wsp.sh Download + transcribe and/or translate any VOD (original)
wchess wchess.wasm Voice-controlled chess

Discussions

If you have any kind of feedback about this project feel free to use the Discussions section and open a new topic. You can use the Show and tell category to share your own projects that use whisper.cpp. If you have a question, make sure to check the Frequently asked questions (#126) discussion.