Core Concepts
Efficient sampling methods, Most Implied Frames (MIF) and Most Dominant Frames (MDF), are proposed to boost the performance of image-text models on video question answering tasks.
Abstract
The content discusses efficient sampling methods for video question answering (VQA) tasks using image-text models (ITMs).
The key points are:
Existing ITM-based VQA approaches either use simplistic and unintentional sampling strategies, which may miss key frames, or sample a large number of frames which is computationally expensive.
The authors propose two efficient sampling methods: Most Implied Frames (MIF) and Most Dominant Frames (MDF).
MIF uses a caption model and a scoring model to select the frames that are most relevant to the given question. It is a question-aware sampling approach.
Based on the analysis of MIF results, the authors hypothesize that question-aware sampling is not necessary. They then propose MDF, a question-agnostic sampling method that selects the most dominant frames in the video.
MDF leverages the inherent vision encoder of the ITM to quantify the dominance of each frame and selects the frames with the lowest dominance score.
Experiments on three ITM backbones (CLIP, GIT, All-in-One) and four VQA datasets show that both MIF and MDF can boost the performance over strong baselines, with MDF being more efficient.
Further analysis reveals that increasing the number of input frames improves performance, and there is no strong correlation between the success rate of MDF and its accuracy.
Stats
The content does not provide any specific numerical data or statistics. It focuses on describing the proposed sampling methods and their evaluation.
Quotes
There are no direct quotes from the content that are particularly striking or support the key logics.