feat(parakeet-cpp): add NVIDIA NeMo Parakeet ASR backend (parakeet.cpp)#10084
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…on (text) Add a Go gRPC backend that bridges LocalAI to parakeet.cpp via the flat C-API (parakeet_capi.h), loaded with purego (cgo-less, mirrors the whisper / vibevoice-cpp backends). L0 scope: - main.go: dlopen libparakeet.so (override via PARAKEET_LIBRARY), register the C-API entry points, start the gRPC server. - goparakeetcpp.go: Load (parakeet_capi_load), AudioTranscription (parakeet_capi_transcribe_path, decoder=0 = per-arch default head), Free, serialized through base.SingleThread since the C engine is a thread-unsafe singleton. char* returns are bound as uintptr so the malloc'd buffer is freed via parakeet_capi_free_string after copy. - AudioTranscriptionStream returns a clear "not implemented in L0" error (closes the channel so the server doesn't hang), wired in L2. - Makefile: clone-at-pin + cmake (PARAKEET_VERSION for bump_deps.sh), with a local-symlink dev shortcut; run.sh / package.sh mirror whisper. - Test auto-skips without PARAKEET_BACKEND_TEST_MODEL/_WAV fixtures. Builds clean (CGO_ENABLED=0), gofmt clean, test passes. The single unsafeptr vet note in goStringFromCPtr is documented and matches the whisper backend's tolerated pattern. Word/segment timestamps (L1) and cache-aware streaming (L2) follow. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
AudioTranscription now calls parakeet_capi_transcribe_path_json and shapes
the per-word / per-token timestamps into the TranscriptResult:
- Bind parakeet_capi_transcribe_path_json (purego, char* as uintptr like
the other returns) and register it in main.go + the test loader.
- Parse the JSON document ({"text","words":[{w,start,end,conf}],
"tokens":[{id,t,conf}]}) into typed structs.
- Synthesise a single whole-clip segment (parakeet emits no native segment
boundaries) spanning the first word start to the last word end; token ids
populate Segment.Tokens.
- Attach word-level timings only when timestamp_granularities=["word"],
matching the OpenAI API (segment-level default). secondsToNanos mirrors
the whisper backend's nanosecond convention.
Verified end-to-end against tdt_ctc-110m (f16): both the default and
word-granularity specs pass; builds clean, gofmt clean, vet shows only the
one documented unsafeptr note shared with the whisper backend.
Cache-aware streaming (L2) follows.
Assisted-by: Claude:claude-opus-4-8 [Claude Code]
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Wire AudioTranscriptionStream to the streaming RNN-T C-API:
- Bind parakeet_capi_stream_{begin,feed,finalize,free}; feed takes 16 kHz
mono float PCM ([]float32 via purego) and writes *eou_out on <EOU>/<EOB>.
- Decode opts.Dst to 16 kHz mono PCM (utils.AudioToWav + go-audio, same as
the whisper backend), feed it in 1 s chunks, and emit each newly-finalized
text run as a TranscriptStreamResponse delta.
- <EOU>/<EOB> events close the current segment; a closing FinalResult carries
the full transcript plus the per-utterance segments (with a whole-clip
fallback segment when no EOU fired).
- stream_begin returns 0 for non-streaming models, surfaced as a clear
error instead of an empty stream. Honours context cancellation between
chunks. Frees every malloc'd delta and the session.
Verified end-to-end against realtime_eou_120m-v1 (f16): the streamed
transcript matches the offline 110m reference word-for-word, deltas
reconstruct the final text, and the spec passes alongside the offline
specs. Builds clean, gofmt clean, vet shows only the shared documented
unsafeptr note.
Assisted-by: Claude:claude-opus-4-8 [Claude Code]
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
…parity) Wire the new Go gRPC parakeet-cpp backend (parakeet.cpp ggml port of NVIDIA NeMo Parakeet ASR) into LocalAI's build/CI/gallery surfaces, matching the existing ggml whisper Go backend 1:1. - .github/backend-matrix.yml: add 11 linux entries + 1 darwin entry mirroring every whisper build (cpu amd64/arm64, intel sycl f32/f16, vulkan amd64/arm64, nvidia cuda-12, nvidia cuda-13, nvidia-l4t-arm64, nvidia-l4t-cuda-13-arm64, rocm hipblas, metal-darwin-arm64), all on ./backend/Dockerfile.golang with backend: "parakeet-cpp" and -*-parakeet-cpp tag-suffixes. - scripts/changed-backends.js: explicit inferBackendPath branch resolving parakeet-cpp to backend/go/parakeet-cpp/ before the generic golang branch. - .github/workflows/bump_deps.yaml: track the PARAKEET_VERSION pin in backend/go/parakeet-cpp/Makefile (repo mudler/parakeet.cpp, branch master). - backend/index.yaml: add ¶keetcpp meta + latest/development image entries for every matrix tag-suffix. - Makefile: add backends/parakeet-cpp to .NOTPARALLEL, BACKEND_PARAKEET_CPP definition, docker-build target eval, and test-extra-backend-parakeet-cpp- transcription target (mirrors test-extra-backend-whisper-transcription). Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Add ParakeetCppImporter so parakeet.cpp GGUFs auto-detect on /import-model and route to the parakeet-cpp backend (it also surfaces in /backends/known, which drives the import dropdown). - Match is narrow: a .gguf whose name carries a parakeet architecture token (<arch>-<size>-<quant>.gguf, e.g. tdt_ctc-110m-f16.gguf, rnnt-0.6b-q4_k.gguf, realtime_eou_120m-v1-q8_0.gguf), a direct URL to one, or preferences.backend="parakeet-cpp". It deliberately does NOT claim arbitrary llama-style GGUFs, nor the upstream nvidia/parakeet-* NeMo repos (.nemo, not runnable here). - Registered in the ASR batch BEFORE LlamaCPPImporter so its GGUFs aren't swallowed by the generic .gguf importer. - Import nests files under parakeet-cpp/models/<name>/, defaults to the smallest quant (q4_k, near-lossless on parakeet) with a size-ladder fallback, and honours preferences.quantizations / name / description. Tested with synthetic HF details (no network): metadata, positive matches (HF repo, direct URL, preference), narrowness negatives (llama GGUF, NeMo repo), and import (default quant, override, direct URL), 9 specs pass, build/vet/gofmt clean. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Add parakeet-cpp to the audio-to-text backend list and a dedicated usage section: direct GGUF import (auto-detects to the backend), model YAML, word-level timestamps via timestamp_granularities[]=word, and cache-aware streaming with the realtime_eou model. Points at the mudler/parakeet-cpp-gguf collection repo. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
The L3 commit added the test-extra-backend-parakeet-cpp-transcription Makefile target but never invoked it in CI. Mirror the whisper job: - Add a parakeet-cpp output to detect-changes (emitted by changed-backends.js from the matrix entry). - Add tests-parakeet-cpp-grpc-transcription, gated on the parakeet-cpp path filter / run-all, building the backend image and running the transcription e2e against tdt_ctc-110m + the JFK clip. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Replace em dashes with plain punctuation in the backend comments, the importer, package.sh, and the audio-to-text docs section (and use "and" instead of the multiplication sign). No behaviour change. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Add the 10 NVIDIA Parakeet models (f16, the recommended quality/speed default) as gallery entries that install on the parakeet-cpp backend from mudler/parakeet-cpp-gguf: tdt_ctc-110m/1.1b, tdt-0.6b-v2/v3, tdt-1.1b, ctc-0.6b/1.1b, rnnt-0.6b/1.1b, and the cache-aware streaming realtime_eou_120m-v1. Each pins the file sha256 and routes transcript usecases to the backend. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
- goparakeetcpp.go: //nolint:govet on the C-owned-pointer unsafe.Pointer conversion (golangci-lint reports new-only issues, so unlike the whisper backend's identical line this one is flagged). - Makefile: bump PARAKEET_VERSION to the current parakeet.cpp master commit (the previous pin's commit no longer exists after upstream history was squashed), so the backend image clone/build resolves again. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
The previous SHA pin was orphaned when parakeet.cpp's single-commit master was amended/force-pushed, so the backend image clone (git fetch <sha>) failed across every build variant. Repoint to 845c29e, which upstream now keeps permanently fetchable via the `localai-backend-pin` tag, so future upstream amends no longer break the backend build. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
The backend Dockerfile clones parakeet.cpp at PARAKEET_VERSION with a shallow fetch + checkout but never initialised submodules, so third_party/ggml was empty and the parakeet.cpp cmake build failed at `add_subdirectory(third_party/ggml)` (CMakeLists.txt:53) on every build variant. Add `git submodule update --init --recursive --depth 1 --single-branch` after checkout, mirroring the whisper backend. Verified locally: clone + submodule + cmake configure now succeeds. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
The shared libparakeet.so linked ggml's shared libs (libggml*.so), but the package only ships libparakeet.so, so at runtime dlopen failed with "libggml.so.0: cannot open shared object file" (the e2e transcription test panicked on load). Build ggml static + PIC (BUILD_SHARED_LIBS=OFF, CMAKE_POSITION_INDEPENDENT_CODE=ON) so libparakeet.so embeds ggml and depends only on system libs already present in the runtime image. Verified locally: ldd shows no libggml dependency. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
The e2e streaming test ran AudioTranscriptionStream against tdt_ctc-110m (not a cache-aware streaming model), so stream_begin returned 0 and the call errored. Per LocalAI's streaming contract (and the whisper backend), a non-streaming model should fall back to a single offline transcription emitted as one delta plus a closing FinalResult. Do that instead of erroring, so the streaming endpoint works for every parakeet model. Verified locally: the streaming spec passes against the non-streaming 110m model via fallback. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
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…10106) parakeet-cpp was added in #10084 but not registered in BackendCapabilities, so GuessUsecases only allowed "whisper" for FLAG_TRANSCRIPT and the UI could not classify parakeet-cpp models as speech-to-text. The result was that parakeet models appeared only in the LLM selector in the speech-to-speech pipeline, making them unusable for transcription through the UI. Closes #9718 Assisted-by: Claude Sonnet 4.6 <noreply@anthropic.com>
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What
Adds a new
parakeet-cppaudio-transcription backend wrapping parakeet.cpp, a C++/ggml port of NVIDIA NeMo Parakeet (FastConformer TDT/CTC/RNNT/hybrid) that matches the upstream PyTorch models on CPU. It's a cgo-less Go gRPC backend (purego over the flatparakeet_capi.h), mirroring thewhisper/vibevoice-cppbackends.Layers
main.godlopenslibparakeet.so,LoadModel,AudioTranscription(text) viaparakeet_capi_transcribe_path, serialized throughbase.SingleThread.AudioTranscriptionusesparakeet_capi_transcribe_path_json; per-word timings attached whentimestamp_granularities[]=word(OpenAI-compatible), token ids populateSegment.Tokens.AudioTranscriptionStreamfeeds 16 kHz mono PCM in chunks tostream_{begin,feed,finalize}, emitting deltas;<EOU>/<EOB>events close per-utterance segments; closingFinalResultcarries the full transcript..github/backend-matrix.yml(cpu, cuda-12/13, ROCm/hipblas, Intel-SYCL f16/f32, Vulkan, L4T, metal-darwin),scripts/changed-backends.js,bump_deps.yaml(tracksPARAKEET_VERSION),backend/index.yamlmetas + images, and rootMakefilewiring.ParakeetCppImporterauto-detects parakeet GGUFs (narrow<arch>-<size>-<quant>.ggufmatch, won't claim arbitrary llama GGUFs or upstream.nemorepos), routes to this backend, surfaces in/backends/known.audio-to-text.mdusage section (import, YAML, word timestamps, streaming).Models
GGUFs for all 10 Parakeet models x 5 quants are published in a single collection repo:
mudler/parakeet-cpp-gguf.Validation
CGO_ENABLED=0, gofmt clean,go vetclean except one documentedunsafeptrnote shared with the whisper backend.tdt_ctc-110mandrealtime_eou_120m-v1models, the streamed transcript matches the offline reference word-for-word.scripts/changed-backends.jsresolution +backend-matrix.yml/index.yamlYAML validated; matrix ↔ index tag-suffixes cross-checked.🤖 Generated with Claude Code