VIVO: Surpassing Human Performance in Novel Object Captioning with Visual Vocabulary Pre-Training
It is highly desirable yet challenging to generate image captions that can describe novel objects which are unseen in caption-labeled training data, a capability that is evaluated in the novel object captioning challenge (nocaps). In this challenge, no additional image-caption training data, other than COCO Captions, is allowed for model training. Thus, conventional Vision-Language Pre-training (VLP) methods cannot be applied. This paper presents VIsual VOcabulary pretraining (VIVO) that performs pre-training in the absence of caption annotations. By breaking the dependency of paired image-caption training data in VLP, VIVO can leverage large amounts of paired image-tag data to learn a visual vocabulary. This is done by pre-training a multi-layer Transformer model that learns to align image-level tags with their corresponding image region features. To address the unordered nature of image tags, VIVO uses a Hungarian matching loss with masked tag prediction to conduct pre-training.
We validate the effectiveness of VIVO by fine-tuning the pre-trained model for image captioning. In addition, we perform an analysis of the visual-text alignment inferred by our model. The results show that our model can not only generate fluent image captions that describe novel objects, but also identify the locations of these objects. Our single model has achieved new state-of-the-art results on nocaps and surpassed the human CIDEr score.
Image captioning is an interesting problem in the intersection between computer vision and natural language processing, and it has attracted great attention from their respective research communities. Recent image captioning models have achieved impressive results on the tasks where large amounts of paired image-caption training data is available. However, they generalize poorly to images in the wild, where there are a wide variety of visual objects that are unseen in the caption corpora for training. This raises the challenge of Novel Object Captioning (NOC), that is, generating captions to describe novel objects unseen in paired image-caption training data, which is especially pertinent in real-world applications. This webinar will focus on some of the recent vision-language pretraining (VLP) approaches for image captioning. We will cover our latest approaches, including object-semantics aligned pretraining (OSCAR) and visual-vocabulary pretraining (VIVO). We will also discuss their key principles and how we address the core challenges in image caption generation. Join us to learn how our discovery leads to a new image captioning framework that achieves state-of-the-art performance on the nocaps benchmark (developed to evaluate NOC at scale) and surpasses human CIDEr scores on nocaps for the first time. Visual-vocabulary pretraining (VIVO) conducts pretraining with vision data only. As the method does not need paired image-caption data, it opens the possibility of leveraging large amounts of images, paired with either human-labeled or machine-generated tags. By using VIVO pretraining, the performance of the captioning model, especially on novel objects, has been substantially improved. What you’ll learn: How latest VLP approaches help to improve captioning performance by pretraining on large-scale image-text pairs, then fine-tuning on task-specific small data. How VIVO pretraining is conducted in the absence of image-text pairs, leading to state-of-the-art performance on NOC. How visual-text alignment is learned during VLP and significantly contributes to the downstream vision-language tasks. How to use our open-source model and code in your research and how to use our Azure Cognitive Services cloud API for your own development. Resource list: Azure Florence Project page Oscar on Github Oscar Publication VIVO Publication Novel object captioning surpasses human performance on benchmarks (MSR Blog) Objects are the secret key to revealing the world between vision and language (MSR Blog) Azure AI, describes images as well as people do (AI Blog) Lijuan Wang (Researcher profile) Xiaowei Hu (Researcher profile) *This on-demand webinar features a previously recorded Q&A session and open captioning. Explore more Microsoft Research webinars: https://aka.ms/msrwebinars