Improved Image Captioning Using GAN and ViT

Encoder-decoder architectures are widely used in solving image captioning applications. Convolutional encoders and recurrent decoders are prominently used for such applications. Recent advances in transformer-based designs have made SOTA performances in solving various language and vision tasks. This work inspects the research question of using transformer-based encoder and decoder in building an effective pipeline for image captioning. An adversarial objective using a Generative Adversarial Network is used to improve the diversity of the captions generated. The generator component of our model utilizes a ViT encoder and a transformer decoder to generate semantically meaningful captions for a given image. To enhance the quality and authenticity of the generated captions, we introduce a discriminator component built using a transformer decoder. The discriminator evaluates the captions by considering both the image and the caption generated by the generator. By training this architecture, we aim to ensure that the generator produces captions that are indistinguishable from real captions, increasing the overall quality of the generated outputs. Through extensive experimentation, we demonstrate the effectiveness of our approach in generating diverse and contextually appropriate captions for various images. We evaluate our model on benchmark datasets and compare its performance against existing state-of-the-art image captioning methods. The proposed approach has achieved superior results compared to previous methods, as demonstrated by improved caption accuracy metrics such as BLEU-3, BLEU-4, and other relevant accuracy measures.