Use CutSet.mux for multidataset (#1020)

* Use CutSet.mux

* Remove mischange

* Fix for style check

egs/librispeech/ASR/prepare_multidataset.sh

@@ -328,46 +328,3 @@ if [ $stage -le 10 ] && [ $stop_stage -ge 10 ]; then
     ./prepare_common_voice.sh
   fi
 fi
-
-if [ $stage -le 11 ] && [ $stop_stage -ge 11 ]; then
-  log "Stage 11: Create multidataset"
-  split_dir=data/fbank/multidataset_split_${num_splits}
-  if [ ! -f data/fbank/multidataset_split/.multidataset.done ]; then
-    mkdir -p $split_dir/multidataset
-    log "Split LibriSpeech"
-    if [ ! -f $split_dir/.librispeech_split.done ]; then
-      lhotse split $num_splits ./data/fbank/librispeech_cuts_train-all-shuf.jsonl.gz $split_dir
-      touch $split_dir/.librispeech_split.done
-    fi
-
-    if [[ "${multidataset[@]}" =~ "gigaspeech" ]]; then
-      log "Split GigaSpeech XL"
-      if [ ! -f $split_dir/.gigaspeech_XL_split.done ]; then
-	cd $split_dir
-        ln -sv ../gigaspeech_XL_split_2000/gigaspeech_cuts_XL.*.jsonl.gz .
-        cd ../../..	
-	touch $split_dir/.gigaspeech_XL_split.done
-      fi
-    fi
-
-    if [[ "${multidataset[@]}" =~ "commonvoice" ]]; then
-      log "Split CommonVoice"
-      if [ ! -f $split_dir/.cv-en_train_split.done ]; then
-        lhotse split $num_splits ./data/en/fbank/cv-en_cuts_train.jsonl.gz $split_dir
-        touch $split_dir/.cv-en_train_split.done
-      fi
-    fi
-
-    if [ ! -f $split_dir/.multidataset_mix.done ]; then
-      log "Mix multidataset"
-      for ((seq=1; seq<=$num_splits; seq++)); do
-	fseq=$(printf "%04d" $seq)
-	gunzip -c $split_dir/*.*${fseq}.jsonl.gz | \
-	  shuf | gzip -c > $split_dir/multidataset/multidataset_cuts_train.${fseq}.jsonl.gz
-      done
-      touch $split_dir/.multidataset_mix.done
-    fi
-
-    touch data/fbank/multidataset_split/.multidataset.done
-  fi
-fi

egs/librispeech/ASR/pruned_transducer_stateless7/multidataset.py

@@ -25,29 +25,53 @@ from lhotse import CutSet, load_manifest_lazy
 
 
 class MultiDataset:
-    def __init__(self, manifest_dir: str):
+    def __init__(self, manifest_dir: str, cv_manifest_dir: str):
         """
         Args:
           manifest_dir:
             It is expected to contain the following files:
 
-            - multidataset_split_1998/multidataset/multidataset_cuts_train.*.jsonl.gz
+            - librispeech_cuts_train-all-shuf.jsonl.gz
+            - gigaspeech_XL_split_2000/gigaspeech_cuts_XL.*.jsonl.gz
+
+          cv_manifest_dir:
+            It is expected to contain the following files:
+
+            - cv-en_cuts_train.jsonl.gz
         """
         self.manifest_dir = Path(manifest_dir)
+        self.cv_manifest_dir = Path(cv_manifest_dir)
 
     def train_cuts(self) -> CutSet:
         logging.info("About to get multidataset train cuts")
 
-        filenames = glob.glob(
-            f"{self.manifest_dir}/multidataset_split_1998/multidataset/multidataset_cuts_train.*.jsonl.gz"
+        # LibriSpeech
+        logging.info(f"Loading LibriSpeech in lazy mode")
+        librispeech_cuts = load_manifest_lazy(
+            self.manifest_dir / "librispeech_cuts_train-all-shuf.jsonl.gz"
         )
 
-        pattern = re.compile(r"multidataset_cuts_train.([0-9]+).jsonl.gz")
+        # GigaSpeech
+        filenames = glob.glob(
+            f"{self.manifest_dir}/gigaspeech_XL_split_2000/gigaspeech_cuts_XL.*.jsonl.gz"
+        )
+
+        pattern = re.compile(r"gigaspeech_cuts_XL.([0-9]+).jsonl.gz")
         idx_filenames = ((int(pattern.search(f).group(1)), f) for f in filenames)
         idx_filenames = sorted(idx_filenames, key=lambda x: x[0])
 
         sorted_filenames = [f[1] for f in idx_filenames]
 
-        logging.info(f"Loading {len(sorted_filenames)} splits")
+        logging.info(f"Loading GigaSpeech {len(sorted_filenames)} splits in lazy mode")
 
-        return lhotse.combine(lhotse.load_manifest_lazy(p) for p in sorted_filenames)
+        gigaspeech_cuts = lhotse.combine(
+            lhotse.load_manifest_lazy(p) for p in sorted_filenames
+        )
+
+        # CommonVoice
+        logging.info(f"Loading CommonVoice in lazy mode")
+        commonvoice_cuts = load_manifest_lazy(
+            self.cv_manifest_dir / f"cv-en_cuts_train.jsonl.gz"
+        )
+
+        return CutSet.mux(librispeech_cuts, gigaspeech_cuts, commonvoice_cuts)

egs/librispeech/ASR/pruned_transducer_stateless7/train.py

@@ -1053,7 +1053,7 @@ def run(rank, world_size, args):
     librispeech = LibriSpeechAsrDataModule(args)
 
     if params.use_multidataset:
-        multidataset = MultiDataset(params.manifest_dir)
+        multidataset = MultiDataset(params.manifest_dir, params.cv_manifest_dir)
         train_cuts = multidataset.train_cuts()
     else:
         if params.full_libri: