* coreml : skip model load in convert-whisper-to-coreml.py This commit updates the conversion process for Whisper models to use the "mlprogram" format instead of "neuralnetwork". The motivation for this change is that when using the "neuralnetwork" format the underlying model produced is based on protobuf and my understanding is that there are limitations to this format, such as sizes of strings and the complexity of the model. Currently when trying to convert larger models such as large-v3 the conversion fails but succeeds for smaller models. The "mlprogram" format is a more recent addition to CoreML and is designed to be more flexible and powerful, allowing for more complex models and larger data types. This seems to work for larger and smaller models alike and unless I'm there are considerations that I'm not aware of I think this is what we should be using moving forward. The error that is generated for large models is the following: ```console Running MIL backend_neuralnetwork pipeline: 100%|█████████| 9/9 [00:00<00:00, 35.44 passes/s] Translating MIL ==> NeuralNetwork Ops: 100%|███████████| 5641/5641 [03:31<00:00, 26.65 ops/s] Traceback (most recent call last): File "/Users/danbev/work/ai/whisper-work/models/convert-whisper-to-coreml.py", line 322, in <module> encoder = convert_encoder(hparams, encoder, quantize=args.quantize) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/danbev/work/ai/whisper-work/models/convert-whisper-to-coreml.py", line 255, in convert_encoder model = ct.convert( ^^^^^^^^^^^ File "/Users/danbev/work/ai/whisper-work/venv/lib/python3.11/site-packages/coremltools/converters/_converters_entry.py", line 635, in convert mlmodel = mil_convert( ^^^^^^^^^^^^ File "/Users/danbev/work/ai/whisper-work/venv/lib/python3.11/site-packages/coremltools/converters/mil/converter.py", line 186, in mil_convert return _mil_convert( ^^^^^^^^^^^^^ File "/Users/danbev/work/ai/whisper-work/venv/lib/python3.11/site-packages/coremltools/converters/mil/converter.py", line 245, in _mil_convert return modelClass( ^^^^^^^^^^^ File "/Users/danbev/work/ai/whisper-work/venv/lib/python3.11/site-packages/coremltools/models/model.py", line 489, in __init__ self.__proxy__, self._spec, self._framework_error = self._get_proxy_and_spec( ^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/danbev/work/ai/whisper-work/venv/lib/python3.11/site-packages/coremltools/models/model.py", line 550, in _get_proxy_and_spec _MLModelProxy( ValueError: basic_string ``` Refs: https://github.com/ggml-org/whisper.cpp/issues/3012
Whisper model files in custom ggml
format
The original Whisper PyTorch models provided by OpenAI
are converted to custom ggml
format in order to be able to load them in C/C++.
Conversion is performed using the convert-pt-to-ggml.py script.
There are three ways to obtain ggml
models:
1. Use download-ggml-model.sh to download pre-converted models
Example download:
$ ./download-ggml-model.sh base.en
Downloading ggml model base.en ...
models/ggml-base.en.bin 100%[=============================================>] 141.11M 5.41MB/s in 22s
Done! Model 'base.en' saved in 'models/ggml-base.en.bin'
You can now use it like this:
$ ./build/bin/whisper-cli -m models/ggml-base.en.bin -f samples/jfk.wav
2. Manually download pre-converted models
ggml
models are available from the following locations:
3. Convert with convert-pt-to-ggml.py
Download one of the models provided by OpenAI and generate the ggml
files using the convert-pt-to-ggml.py script.
Example conversion, assuming the original PyTorch files have been downloaded into ~/.cache/whisper
. Change ~/path/to/repo/whisper/
to the location for your copy of the Whisper source:
mkdir models/whisper-medium
python models/convert-pt-to-ggml.py ~/.cache/whisper/medium.pt ~/path/to/repo/whisper/ ./models/whisper-medium
mv ./models/whisper-medium/ggml-model.bin models/ggml-medium.bin
rmdir models/whisper-medium
Available models
Model | Disk | SHA |
---|---|---|
tiny | 75 MiB | bd577a113a864445d4c299885e0cb97d4ba92b5f |
tiny.en | 75 MiB | c78c86eb1a8faa21b369bcd33207cc90d64ae9df |
base | 142 MiB | 465707469ff3a37a2b9b8d8f89f2f99de7299dac |
base.en | 142 MiB | 137c40403d78fd54d454da0f9bd998f78703390c |
small | 466 MiB | 55356645c2b361a969dfd0ef2c5a50d530afd8d5 |
small.en | 466 MiB | db8a495a91d927739e50b3fc1cc4c6b8f6c2d022 |
small.en-tdrz | 465 MiB | b6c6e7e89af1a35c08e6de56b66ca6a02a2fdfa1 |
medium | 1.5 GiB | fd9727b6e1217c2f614f9b698455c4ffd82463b4 |
medium.en | 1.5 GiB | 8c30f0e44ce9560643ebd10bbe50cd20eafd3723 |
large-v1 | 2.9 GiB | b1caaf735c4cc1429223d5a74f0f4d0b9b59a299 |
large-v2 | 2.9 GiB | 0f4c8e34f21cf1a914c59d8b3ce882345ad349d6 |
large-v2-q5_0 | 1.1 GiB | 00e39f2196344e901b3a2bd5814807a769bd1630 |
large-v3 | 2.9 GiB | ad82bf6a9043ceed055076d0fd39f5f186ff8062 |
large-v3-q5_0 | 1.1 GiB | e6e2ed78495d403bef4b7cff42ef4aaadcfea8de |
large-v3-turbo | 1.5 GiB | 4af2b29d7ec73d781377bfd1758ca957a807e941 |
large-v3-turbo-q5_0 | 547 MiB | e050f7970618a659205450ad97eb95a18d69c9ee |
Models are multilingual unless the model name includes .en
. Models ending in -q5_0
are quantized. Models ending in -tdrz
support local diarization (marking of speaker turns) using tinydiarize. More information about models is available upstream (openai/whisper). The list above is a subset of the models supported by the download-ggml-model.sh script, but many more are available at https://huggingface.co/ggerganov/whisper.cpp/tree/main and elsewhere.
Model files for testing purposes
The model files prefixed with for-tests-
are empty (i.e. do not contain any weights) and are used by the CI for
testing purposes. They are directly included in this repository for convenience and the Github Actions CI uses them to
run various sanitizer tests.
Fine-tuned models
There are community efforts for creating fine-tuned Whisper models using extra training data. For example, this blog post describes a method for fine-tuning using Hugging Face (HF) Transformer implementation of Whisper. The produced models are in slightly different format compared to the original OpenAI format. To read the HF models you can use the convert-h5-to-ggml.py script like this:
git clone https://github.com/openai/whisper
git clone https://github.com/ggml-org/whisper.cpp
# clone HF fine-tuned model (this is just an example)
git clone https://huggingface.co/openai/whisper-medium
# convert the model to ggml
python3 ./whisper.cpp/models/convert-h5-to-ggml.py ./whisper-medium/ ./whisper .
Distilled models
Initial support for https://huggingface.co/distil-whisper is available.
Currently, the chunk-based transcription strategy is not implemented, so there can be sub-optimal quality when using the distilled models with whisper.cpp
.
# clone OpenAI whisper and whisper.cpp
git clone https://github.com/openai/whisper
git clone https://github.com/ggml-org/whisper.cpp
# get the models
cd whisper.cpp/models
git clone https://huggingface.co/distil-whisper/distil-medium.en
git clone https://huggingface.co/distil-whisper/distil-large-v2
# convert to ggml
python3 ./convert-h5-to-ggml.py ./distil-medium.en/ ../../whisper .
mv ggml-model.bin ggml-medium.en-distil.bin
python3 ./convert-h5-to-ggml.py ./distil-large-v2/ ../../whisper .
mv ggml-model.bin ggml-large-v2-distil.bin