decoder for open vocabulary keyword spotting (#505)

* various fixes to ContextGraph to support open vocabulary keywords decoder

* Add keyword spotter runtime

* Add binary

* First version works

* Minor fixes

* update text2token

* default values

* Add jni for kws

* add kws android project

* Minor fixes

* Remove unused interface

* Minor fixes

* Add workflow

* handle extra info in texts

* Minor fixes

* Add more comments

* Fix ci

* fix cpp style

* Add input box in android demo so that users can specify their keywords

* Fix cpp style

* Fix comments

* Minor fixes

* Minor fixes

* minor fixes

* Minor fixes

* Minor fixes

* Add CI

* Fix code style

* cpplint

* Fix comments

* Fix error

.github/scripts/test-kws.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+set -e
+
+log() {
+  # This function is from espnet
+  local fname=${BASH_SOURCE[1]##*/}
+  echo -e "$(date '+%Y-%m-%d %H:%M:%S') (${fname}:${BASH_LINENO[0]}:${FUNCNAME[1]}) $*"
+}
+
+echo "EXE is $EXE"
+echo "PATH: $PATH"
+
+which $EXE
+
+log "------------------------------------------------------------"
+log "Run Chinese keyword spotting (Wenetspeech）"
+log "------------------------------------------------------------"
+
+repo_url=https://www.modelscope.cn/pkufool/sherpa-onnx-kws-zipformer-wenetspeech-3.3M-2024-01-01.git
+log "Start testing ${repo_url}"
+repo=sherpa-onnx-kws-zipformer-wenetspeech-3.3M-2024-01-01
+log "Download pretrained model and test-data from $repo_url"
+
+GIT_LFS_SKIP_SMUDGE=1 git clone $repo_url
+pushd $repo
+git lfs pull --include "*.onnx"
+ls -lh *.onnx
+popd
+
+time $EXE \
+  --tokens=$repo/tokens.txt \
+  --encoder=$repo/encoder-epoch-12-avg-2-chunk-16-left-64.onnx \
+  --decoder=$repo/decoder-epoch-12-avg-2-chunk-16-left-64.onnx \
+  --joiner=$repo/joiner-epoch-12-avg-2-chunk-16-left-64.onnx \
+  --keywords-file=$repo/test_wavs/test_keywords.txt \
+  --max-active-paths=4 \
+  --num-threads=4 \
+  $repo/test_wavs/3.wav $repo/test_wavs/4.wav $repo/test_wavs/5.wav $repo/test_wavs/6.wav
+
+rm -rf $repo
+
+log "------------------------------------------------------------"
+log "Run English keyword spotting (Gigaspeech）"
+log "------------------------------------------------------------"
+
+repo_url=https://www.modelscope.cn/pkufool/sherpa-onnx-kws-zipformer-gigaspeech-3.3M-2024-01-01.git
+log "Start testing ${repo_url}"
+repo=sherpa-onnx-kws-zipformer-gigaspeech-3.3M-2024-01-01
+log "Download pretrained model and test-data from $repo_url"
+
+GIT_LFS_SKIP_SMUDGE=1 git clone $repo_url
+pushd $repo
+git lfs pull --include "*.onnx"
+ls -lh *.onnx
+popd
+
+time $EXE \
+  --tokens=$repo/tokens.txt \
+  --encoder=$repo/encoder-epoch-12-avg-2-chunk-16-left-64.onnx \
+  --decoder=$repo/decoder-epoch-12-avg-2-chunk-16-left-64.onnx \
+  --joiner=$repo/joiner-epoch-12-avg-2-chunk-16-left-64.onnx \
+  --keywords-file=$repo/test_wavs/test_keywords.txt \
+  --max-active-paths=4 \
+  --num-threads=4 \
+  $repo/test_wavs/0.wav $repo/test_wavs/1.wav
+
+rm -rf $repo