Support multimodal use cases

[julian-risch]

Haystack 2.0 documents support more than just text data but multimodal uses cases require tailored components. This epic issue is about enabling one of those use cases and getting an understanding of what blocks other use cases. Focus should be on preprocessors, retrievers and readers/generators for Table QA.

Table QA
Includes better preprocessing for example for tables split across multiple PDF pages, retrievers, and readers/generators

Visual QA
Answering questions about the content of images in general using both visual and textual information

Image Captioning
Indexing images and creating captions for better retrieval

Speech-to-Text and Text-to-Speech
(in addition to our WhisperTranscriber components)

Tasks

Beta Give feedback

1. Add image generation support for Gemini integration haystack-core-integrations#485
   feature request integration:google-ai +2
2. Support Multimodal (and Table) Embedding #5943
   2.x P3 +2

[julian-risch]

Related issue about multimodal embedding #5943