| --- |
| license: cc-by-4.0 |
| pretty_name: Lombard GRID Cross-Modal Utterance Retrieval |
| task_categories: |
| - any-to-any |
| tags: |
| - mteb |
| - moeb |
| - audio-video-retrieval |
| - cross-view-retrieval |
| - speech-retrieval |
| dataset_info: |
| - config_name: condition_pairs |
| features: |
| - name: plain_recording_id |
| dtype: string |
| - name: lombard_recording_id |
| dtype: string |
| splits: |
| - name: test |
| num_bytes: 23760 |
| num_examples: 540 |
| download_size: 13102 |
| dataset_size: 23760 |
| - config_name: matching_utterances |
| features: |
| - name: audio_id |
| dtype: string |
| - name: front_video_id |
| dtype: string |
| - name: profile_video_id |
| dtype: string |
| splits: |
| - name: test |
| num_bytes: 36720 |
| num_examples: 540 |
| download_size: 19393 |
| dataset_size: 36720 |
| - config_name: media |
| features: |
| - name: recording_id |
| dtype: string |
| - name: audio_id |
| dtype: string |
| - name: front_video_id |
| dtype: string |
| - name: profile_video_id |
| dtype: string |
| - name: front_video |
| dtype: video |
| - name: profile_video |
| dtype: video |
| - name: audio |
| dtype: audio |
| splits: |
| - name: test |
| num_bytes: 538091712 |
| num_examples: 1080 |
| download_size: 498569082 |
| dataset_size: 538091712 |
| configs: |
| - config_name: condition_pairs |
| data_files: |
| - split: test |
| path: condition_pairs/test-* |
| - config_name: matching_utterances |
| data_files: |
| - split: test |
| path: matching_utterances/test-* |
| - config_name: media |
| data_files: |
| - split: test |
| path: media/test-* |
| --- |
| |
| # Lombard GRID Cross-Modal Utterance Retrieval |
|
|
| Four MTEB/MOEB utterance-retrieval tasks derived from the |
| [Lombard GRID corpus](https://zenodo.org/records/3736465): audio-to-video, video-to-audio, |
| frontal-to-profile video, and plain-to-Lombard video+audio. Relevance always |
| requires the same utterance recording or the same speaker-and-sentence pair; |
| speaker identity alone is never relevant. |
|
|
| The source paper introduced the corpus but did not define these retrieval tasks. |
| Relevance is derived from native recording, speaker, sentence-code, condition, |
| and camera-view labels. |
|
|
| ## Frozen evaluation protocol |
|
|
| - Speakers: 54 (`s2` through `s55`; `s1` was excluded by the source) |
| - Selected sentence codes: 540 (10 per speaker) |
| - Published media recordings: 1080 |
| - Matching-task recordings: 540 (5 plain and 5 Lombard per speaker) |
| - Selection seed: `mteb-lombard-grid-retrieval-v2` |
|
|
| For every speaker, eligible sentence codes present in both conditions and all |
| three media streams are ordered by SHA-256 over the fixed seed, speaker, and |
| sentence code. The first ten valid pairs are retained. Five plain and five |
| Lombard recordings per speaker are then selected deterministically for the three |
| same-recording tasks. Opaque IDs are published; speaker, condition, sentence |
| code, transcription, and other text are not encodable dataset features. |
|
|
| | Task | Queries | Corpus | Qrels | Positives/query | |
| |---|---:|---:|---:|---:| |
| | Audio to frontal/profile video | 540 | 1,080 | 1,080 | 2 | |
| | Frontal/profile video to audio | 1,080 | 540 | 1,080 | 1 | |
| | Frontal video to profile video | 540 | 540 | 540 | 1 | |
| | Plain frontal video+audio to Lombard frontal video+audio | 540 | 540 | 540 | 1 | |
|
|
| ## Source audit and release discrepancies |
|
|
| The official JSON archive contains 5,340 rows, while each |
| media archive contains 5,390 files. All three |
| media archives have exactly the same recording filenames. The media restore 50 |
| `s31` recordings absent from JSON. `s51` has only 40 plain and 50 Lombard files, |
| rather than the advertised 50 of each. `s14` has 51 plain and 49 Lombard rows, |
| including a duplicate `prwr3a` recording key. The JSON metadata labels 69 |
| recordings as `WRONG`. Media filenames mark 70: the additional one is among the |
| 50 media-only `s31` recordings. All 70, plus the one legacy-named duplicate, are |
| excluded from selection. Four frontal MOV files lack a `moov` atom and are corrupt: |
| `s32_l_pwip9p`, `s32_p_bwwj2n`, `s33_l_pwajza`, and `s33_p_sgwq2s`. |
|
|
| The deterministic selection required 0 fallback(s). The selected |
| protocol remains exactly balanced after exclusions. |
|
|
| ## Media processing and validation |
|
|
| The released MOV files are already H.264/yuv420p visual-only clips, so |
| 2,160 selected videos are copied without |
| transcoding. 0 video(s) required a lossless video-stream remux to |
| remove embedded audio. Separate source WAV files are copied without transcoding. |
|
|
| All 1080 frontal videos, |
| 1080 profile videos, and |
| 1080 audio files were decoded |
| completely with TorchCodec during construction. Matching source filename stems |
| establish audiovisual correspondence. Selected video/audio duration differences |
| were checked and paired decoding succeeded. The source paper reports |
| correlation-based audiovisual alignment before utterance extraction; this |
| construction did **not** independently verify signal-level synchronization. |
|
|
| The shared configs avoid storing the same media repeatedly across four tasks: |
|
|
| - `media/test`: opaque recording and modality IDs, frontal video, profile video, audio |
| - `matching_utterances/test`: opaque audio, frontal-video, and profile-video IDs |
| - `condition_pairs/test`: opaque plain- and Lombard-recording IDs |
|
|
| The MTEB task loaders project these configs into the standard query, corpus, and |
| qrel structures without exposing source labels to embedding models. |
|
|
| ## Evaluation |
|
|
| The primary metric for all four tasks is nDCG@10. Other standard MTEB retrieval |
| metrics are reported as secondary results. These protocols are newly derived, so |
| there is no source-paper retrieval score to reproduce. |
|
|
| ## License and attribution |
|
|
| The source corpus is released under the |
| [Creative Commons Attribution 4.0 International license](https://creativecommons.org/licenses/by/4.0/). |
| Please attribute the original authors and cite the paper below. The MTEB task |
| metadata and this card both use `cc-by-4.0`. |
|
|
| ## Responsible use |
|
|
| The source contains identifiable faces and voices. Although these tasks evaluate |
| utterance correspondence rather than biometric identification, the representations |
| may still encode identity and demographic attributes. Users should consider |
| participant consent, privacy, applicable biometric-data law, subgroup behavior, |
| and downstream misuse before training or deploying related systems. |
|
|
| ## Citation |
|
|
| ```bibtex |
| @article{alghamdi2018corpus, |
| author = {Alghamdi, Najwa and Maddock, Steve and Marxer, Ricard and Barker, Jon and Brown, Guy J.}, |
| title = {A corpus of audio-visual Lombard speech with frontal and profile views}, |
| journal = {The Journal of the Acoustical Society of America}, |
| volume = {143}, |
| number = {6}, |
| pages = {EL523--EL529}, |
| year = {2018}, |
| doi = {10.1121/1.5042758}, |
| } |
| ``` |
|
|
