字幕（替代）的语音翻译是通过将符合特定显示指南的字幕划分插入字幕中断，将语音数据自动转化为良好的字幕。与语音翻译（ST）类似，模型训练需要并行数据，其中包括音频输入与其文本翻译配对。然而，在替代方面，还必须用字幕断裂来注释文本。到目前为止，这一要求代表了系统开发的瓶颈，如公开可用的替代公司所证实。为了填补这一空白，我们提出了一种在不干预的情况下将现有的ST Corpora转换为替代资源的方法。我们构建了一个分段模型，该模型通过以多模式的方式利用音频和文本来自动将文本片段分为适当的字幕，从而在零拍摄条件下实现了高分子的质量。对手动和自动分割培训的替代系统的比较实验导致相似的性能，显示了我们方法的有效性。

自动副标题是将视听产品的语音自动转化为短文本的任务，换句话说，字幕及其相应的时间戳。生成的字幕需要符合多个空间和时间要求（长度，阅读速度），同时与语音同步并以促进理解的方式进行分割。鉴于其相当大的复杂性，迄今为止，通过分别处理转录，翻译，分割为字幕并预测时间戳的元素来解决自动字幕。在本文中，我们提出了第一个直接自动字幕模型，该模型在单个解决方案中从源语音中生成目标语言字幕及其时间戳。与经过内外数据和外域数据训练的最先进的级联模型的比较表明，我们的系统提供了高质量的字幕，同时在整合性方面也具有竞争力，并具有维护单个模型的所有优势。

语音翻译模型无法直接处理较长的音频，例如TED Talks，必须将其分为较短的段。语音翻译数据集提供了音频的手动分割，这些音频在现实世界中不可用，而现有的分割方法通常会在推理时大大降低翻译质量。为了弥合训练的手动分割与推理的自动分割之间的差距，我们提出了有监督的混合音频分割（SHAS），该方法可以有效地从任何手动分段语音语料库中学习最佳分割。首先，我们使用预先训练的WAV2VEC 2.0的语音表示形式来训练分类器，以识别分段中所包含的帧。然后，通过概率分裂和诱导算法找到最佳的分裂点，该算法逐渐在最低概率的框架下逐渐分裂，直到所有段都低于预先指定的长度为止。在Mast-C和MedX上进行的实验表明，通过我们的方法生成的片段的翻译方法将手动分割的质量在5个语言对上进行质量。也就是说，SHAS保留了手动细分的95-98％的BLEU分数，而现有方法的87-93％。我们的方法还可以推广到不同的域，并以看不见的语言实现高零弹性性能。

We present SpeechMatrix, a large-scale multilingual corpus of speech-to-speech translations mined from real speech of European Parliament recordings. It contains speech alignments in 136 language pairs with a total of 418 thousand hours of speech. To evaluate the quality of this parallel speech, we train bilingual speech-to-speech translation models on mined data only and establish extensive baseline results on EuroParl-ST, VoxPopuli and FLEURS test sets. Enabled by the multilinguality of SpeechMatrix, we also explore multilingual speech-to-speech translation, a topic which was addressed by few other works. We also demonstrate that model pre-training and sparse scaling using Mixture-of-Experts bring large gains to translation performance. The mined data and models are freely available.

我们提出了一种两阶段的培训方法，用于开发单个NMT模型，以翻译英语和英语的看不见的语言。对于第一阶段，我们将编码器模型初始化以鉴定XLM-R和Roberta的权重，然后对25种语言的平行数据进行多种语言微调。我们发现该模型可以推广到对看不见的语言的零击翻译。在第二阶段，我们利用这种概括能力从单语数据集生成合成的并行数据，然后用连续的反向翻译训练。最终模型扩展到了英语到许多方向，同时保持了多到英语的性能。我们称我们的方法为ecxtra（以英语为中心的跨语言（x）转移）。我们的方法依次利用辅助并行数据和单语言数据，并且在概念上很简单，仅在两个阶段都使用标准的跨熵目标。最终的ECXTRA模型对8种低资源语言的无监督NMT进行了评估，该语言为英语至哈萨克语（22.3> 10.4 bleu）以及其他15个翻译方向的竞争性能而获得了新的最先进。

End-to-End speech-to-speech translation (S2ST) is generally evaluated with text-based metrics. This means that generated speech has to be automatically transcribed, making the evaluation dependent on the availability and quality of automatic speech recognition (ASR) systems. In this paper, we propose a text-free evaluation metric for end-to-end S2ST, named BLASER, to avoid the dependency on ASR systems. BLASER leverages a multilingual multimodal encoder to directly encode the speech segments for source input, translation output and reference into a shared embedding space and computes a score of the translation quality that can be used as a proxy to human evaluation. To evaluate our approach, we construct training and evaluation sets from more than 40k human annotations covering seven language directions. The best results of BLASER are achieved by training with supervision from human rating scores. We show that when evaluated at the sentence level, BLASER correlates significantly better with human judgment compared to ASR-dependent metrics including ASR-SENTBLEU in all translation directions and ASR-COMET in five of them. Our analysis shows combining speech and text as inputs to BLASER does not increase the correlation with human scores, but best correlations are achieved when using speech, which motivates the goal of our research. Moreover, we show that using ASR for references is detrimental for text-based metrics.

This paper demonstrates that multilingual denoising pre-training produces significant performance gains across a wide variety of machine translation (MT) tasks. We present mBART -a sequence-to-sequence denoising auto-encoder pre-trained on large-scale monolingual corpora in many languages using the BART objective . mBART is the first method for pre-training a complete sequence-to-sequence model by denoising full texts in multiple languages, while previous approaches have focused only on the encoder, decoder, or reconstructing parts of the text. Pre-training a complete model allows it to be directly fine tuned for supervised (both sentence-level and document-level) and unsupervised machine translation, with no task-specific modifications. We demonstrate that adding mBART initialization produces performance gains in all but the highest-resource settings, including up to 12 BLEU points for low resource MT and over 5 BLEU points for many document-level and unsupervised models. We also show it also enables new types of transfer to language pairs with no bi-text or that were not in the pre-training corpus, and present extensive analysis of which factors contribute the most to effective pre-training.

We present a new approach to perform zero-shot cross-modal transfer between speech and text for translation tasks. Multilingual speech and text are encoded in a joint fixed-size representation space. Then, we compare different approaches to decode these multimodal and multilingual fixed-size representations, enabling zero-shot translation between languages and modalities. All our models are trained without the need of cross-modal labeled translation data. Despite a fixed-size representation, we achieve very competitive results on several text and speech translation tasks. In particular, we significantly improve the state-of-the-art for zero-shot speech translation on Must-C. Incorporating a speech decoder in our framework, we introduce the first results for zero-shot direct speech-to-speech and text-to-speech translation.

Data scarcity is one of the main issues with the end-to-end approach for Speech Translation, as compared to the cascaded one. Although most data resources for Speech Translation are originally document-level, they offer a sentence-level view, which can be directly used during training. But this sentence-level view is single and static, potentially limiting the utility of the data. Our proposed data augmentation method SegAugment challenges this idea and aims to increase data availability by providing multiple alternative sentence-level views of a dataset. Our method heavily relies on an Audio Segmentation system to re-segment the speech of each document, after which we obtain the target text with alignment methods. The Audio Segmentation system can be parameterized with different length constraints, thus giving us access to multiple and diverse sentence-level views for each document. Experiments in MuST-C show consistent gains across 8 language pairs, with an average increase of 2.2 BLEU points, and up to 4.7 BLEU for lower-resource scenarios in mTEDx. Additionally, we find that SegAugment is also applicable to purely sentence-level data, as in CoVoST, and that it enables Speech Translation models to completely close the gap between the gold and automatic segmentation at inference time.

我们介绍了CVSS，这是一种大规模的多语言对语音转换（S2ST）语料库，从21种语言覆盖了21种语言的句子级并行S2ST对。通过将Covost 2从Covost 2的翻译文本综合将翻译文本与最先进的TTS系统合成语音，源自公共语音语音语料库和COVOST 2语音到文本转换（ST）语料库。提供了两个版本的翻译演讲：1）CVSS-C：所有翻译演讲都是一种高质量的规范声音; 2）CVSS-T：翻译语音从相应的源语音传输。此外，CVSS提供标准化的翻译文本，它与翻译语音中的发音匹配。在每个版本的CVSS上，我们建立了基线多语言直接S2ST模型和Cascade S2ST模型，验证了语料库的有效性。为了构建强大的Cascade S2ST基准，我们在Covost 2上培训了St模型，这优于前一种最先进的培训，而无需额外的数据。尽管如此，直接S2ST模型的性能在从头开始训练时接近强级联基线，并且在匹配ST模型中初始化时，仅在ASR转换转换时的0.1或0.7bleu差异。

语言模型预训练的最新进展利用大规模数据集创建多语言模型。但是，这些数据集中大多遗漏了低资源语言。这主要是因为网络上没有很好地表示口语，因此被排除在用于创建数据集的大规模爬网中。此外，这些模型的下游用户仅限于最初选择用于预训练的语言的选择。这项工作调查了如何最佳利用现有的预培训模型来为16种非洲语言创建低资源翻译系统。我们关注两个问题：1）如何将预训练的模型用于初始预培训中未包含的语言？ 2）生成的翻译模型如何有效地转移到新域？为了回答这些问题，我们创建了一个新的非洲新闻语料库，涵盖16种语言，其中8种语言不属于任何现有评估数据集的一部分。我们证明，将两种语言转移到其他语言和其他领域的最有效策略是，以少量的高质量翻译数据微调大型预训练模型。

We propose a simple solution to use a single Neural Machine Translation (NMT) model to translate between multiple languages. Our solution requires no changes to the model architecture from a standard NMT system but instead introduces an artificial token at the beginning of the input sentence to specify the required target language. The rest of the model, which includes an encoder, decoder and attention module, remains unchanged and is shared across all languages. Using a shared wordpiece vocabulary, our approach enables Multilingual NMT using a single model without any increase in parameters, which is significantly simpler than previous proposals for Multilingual NMT. On the WMT'14 benchmarks, a single multilingual model achieves comparable performance for English→French and surpasses state-of-the-art results for English→German. Similarly, a single multilingual model surpasses state-of-the-art results for French→English and German→English on WMT'14 and WMT'15 benchmarks, respectively. On production corpora, multilingual models of up to twelve language pairs allow for better translation of many individual pairs. In addition to improving the translation quality of language pairs that the model was trained with, our models can also learn to perform implicit bridging between language pairs never seen explicitly during training, showing that transfer learning and zero-shot translation is possible for neural translation. Finally, we show analyses that hints at a universal interlingua representation in our models and show some interesting examples when mixing languages.

以前的工作主要侧重于改善NLU任务的交叉传输，具有多语言预用编码器（MPE），或提高与伯特的监督机器翻译的性能。然而，探索了，MPE是否可以有助于促进NMT模型的交叉传递性。在本文中，我们专注于NMT中的零射频转移任务。在此任务中，NMT模型培训，只有一个语言对的并行数据集和搁置架MPE，然后它直接测试在零拍语言对上。我们为此任务提出了Sixt，一个简单而有效的模型。 SIXT利用了两阶段培训计划利用MPE，并进一步改进了解离编码器和容量增强的解码器。使用此方法，SIMPT显着优于MBart，这是一个用于NMT的预磨削的多语言编码器解码器模型，平均改善了14个源语言的零拍摄的任何英语测试集上的7.1 BLEU。此外，培训计算成本和培训数据较少，我们的模型在15个任何英语测试组上实现了比Criss和M2M-100，两个强大的多语言NMT基线更好的性能。

多语种NMT已成为MT在生产中部署的有吸引力的解决方案。但是要匹配双语质量，它符合较大且较慢的型号。在这项工作中，我们考虑了几种方法在推理时更快地使多语言NMT变得更快而不会降低其质量。我们在两种20语言多平行设置中尝试几个“光解码器”架构：在TED会谈中小规模和帕拉克曲线上的大规模。我们的实验表明，将具有词汇过滤的浅解码器组合在于，在翻译质量下没有损失的速度超过两倍。我们用Bleu和Chrf（380语言对），鲁棒性评估和人类评估验证了我们的研究结果。

As machine translation (MT) metrics improve their correlation with human judgement every year, it is crucial to understand the limitations of such metrics at the segment level. Specifically, it is important to investigate metric behaviour when facing accuracy errors in MT because these can have dangerous consequences in certain contexts (e.g., legal, medical). We curate ACES, a translation accuracy challenge set, consisting of 68 phenomena ranging from simple perturbations at the word/character level to more complex errors based on discourse and real-world knowledge. We use ACES to evaluate a wide range of MT metrics including the submissions to the WMT 2022 metrics shared task and perform several analyses leading to general recommendations for metric developers. We recommend: a) combining metrics with different strengths, b) developing metrics that give more weight to the source and less to surface-level overlap with the reference and c) explicitly modelling additional language-specific information beyond what is available via multilingual embeddings.

本文介绍了我们针对IWSLT 2022离线任务的端到端Yitrans语音翻译系统的提交，该任务从英语音频转换为德语，中文和日语。 Yitrans系统建立在大规模训练的编码器模型上。更具体地说，我们首先设计了多阶段的预训练策略，以建立具有大量标记和未标记数据的多模式模型。然后，我们为下游语音翻译任务微调模型的相应组件。此外，我们做出了各种努力，以提高性能，例如数据过滤，数据增强，语音细分，模型集合等。实验结果表明，我们的Yitrans系统比在三个翻译方向上的强基线取得了显着改进，并且比去年在TST2021英语 - 德国人中的最佳端到端系统方面的改进+5.2 BLEU改进。根据自动评估指标，我们的最终意见在英语 - 德国和英语端到端系统上排名第一。我们使代码和模型公开可用。

在本文中，我们分享了我们努力建立能够翻译一千多种语言的实用机器翻译（MT）系统的发现。我们在三个研究领域中描述了结果：（i）通过利用半监督预训练的语言识别和开发数据驱动的过滤技术来构建1500多种语言的清洁，网挖数据集； （ii）通过利用大规模的多语言模型来开发用于服务不足的语言的实用MT模型，该模型训练了有监督的并行数据，以使用100多种高资源语言和单语言数据集，以增加1000多种语言； （iii）研究这些语言的评估指标的局限性，并对我们MT模型的输出进行定性分析，突出显示了这些类型模型的几种频繁误差模式。我们希望我们的工作为旨在为当前研究的语言构建MT系统的从业者提供有用的见解，并突出显示可以补充Data-Sparse设置中大量多语言模型的弱点的研究方向。

在所有人类语言对之间实现通用翻译是机器翻译的圣杯（MT）研究。虽然最近在大量的多语言MT中的进展是达到这一目标的一步，但它变得明显，即简单地通过在更加平行数据上训练扩展多语言MT系统是不可编译的，因为用于低资源和非英语的标记数据的可用性 - 姓氏对禁止有限。为此，我们展示了一种务实的方法，可以使用监督和自我监督目标的混合来构建涵盖数百种语言的多语种MT模型，具体取决于不同语言对的数据可用性。我们展示这两种训练范例之间的协同作用使模型能够在零资源设置中产生高质量的翻译，甚至超过监控的用于中资和中资和中资质。我们开展广泛的实验，了解多语言监督，域错配和平行和单机数据量的效果，以了解我们自我监督的多语言模型的质量。为了展示方法的可扩展性，我们培训具有200多种语言的模型，并在几个先前研究的语言上展示了对零资源翻译的高性能。我们希望我们的调查结果将成为踏脚石，以便为下一千种语言进行翻译。

Speech translation (ST) is the task of directly translating acoustic speech signals in a source language into text in a foreign language. ST task has been addressed, for a long time, using a pipeline approach with two modules : first an Automatic Speech Recognition (ASR) in the source language followed by a text-to-text Machine translation (MT). In the past few years, we have seen a paradigm shift towards the end-to-end approaches using sequence-to-sequence deep neural network models. This paper presents our efforts towards the development of the first Broadcast News end-to-end Arabic to English speech translation system. Starting from independent ASR and MT LDC releases, we were able to identify about 92 hours of Arabic audio recordings for which the manual transcription was also translated into English at the segment level. These data was used to train and compare pipeline and end-to-end speech translation systems under multiple scenarios including transfer learning and data augmentation techniques.

Multilingual pretrained models are effective for machine translation and cross-lingual processing because they contain multiple languages in one model. However, they are pretrained after their tokenizers are fixed; therefore it is difficult to change the vocabulary after pretraining. When we extend the pretrained models to new languages, we must modify the tokenizers simultaneously. In this paper, we add new subwords to the SentencePiece tokenizer to apply a multilingual pretrained model to new languages (Inuktitut in this paper). In our experiments, we segmented Inuktitut sentences into subwords without changing the segmentation of already pretrained languages, and applied the mBART-50 pretrained model to English-Inuktitut translation.