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Vision language models are blind

vlmsareblind.github.io

81–90 of 202 posts

Re: Vision language models are blind

#81

A few comments below talk about how tokenizing images using stuff like CLIP de-facto yields blurry image descriptions, and so these are ‘blind’ by some definitions. Another angle of blurring not much discussed is that the images are rescaled down; different resolutions for different models. I wouldn’t be surprised if Sonnet 3.5 had a higher res base image it feeds in to the model. Either way, I would guess that we’ll…

The problem with the current crop of projectors such as LLaVA is that as far as I know do not take the previous conversation into account. You only really get zero shot responses. This means that you cannot steer the model towards paying attention to specific instruction related details. The projector simply creates a token representation of the visuals (not necessarily human language tokens) and the LLM just process…

The original gpt4 did this too, it had almost no memory before or after the image provided. I haven’t tested gpt4o on this directly, but my feeling is that it’s better from casual usage.

I do think some of these thin line drawings are likely extra hard to tokenize depending on the image scaling sizes for tokenization. I’d wager thicker lines would help, although obviously not all of this is just ‘poor tokenization’.

Re: Vision language models are blind

#82
post #45

Speaking as someone with only a tenuous grasp of how VLMs work, this naïvely feels like a place where the "embodiement" folks might have a point: Humans have the ability to "refine" their perception of an image iteratively, focusing in on areas of interest, while VLMs have to process the entire image at the same level of fidelity. I'm curious if there'd be a way to emulate this (have the visual tokens be low fidelity…

>Humans have the ability to "refine" their perception of an image iteratively That's not related to embodied cognition.

Is embodied cognition not at least in part about interactivity? I perform action (emit tokens) and receive feedback (non-self-generated tokens)

Re: Vision language models are blind

#83
post #45

Speaking as someone with only a tenuous grasp of how VLMs work, this naïvely feels like a place where the "embodiement" folks might have a point: Humans have the ability to "refine" their perception of an image iteratively, focusing in on areas of interest, while VLMs have to process the entire image at the same level of fidelity. I'm curious if there'd be a way to emulate this (have the visual tokens be low fidelity…

Lots and lots of eye tracking data paired with what was being looked at in order to emulate human attention processing might be one of the lower hanging fruits for improving it.

Re: Vision language models are blind

#84
post #53
post #4

Current approaches of multi-modal models work on embeddings and tokenizations of images, which is the fundamental problem: you are feeding blurry, non-precise data into the model. Yes, they are blind because of exactly this. An embedding isn't conceptually that much different from feeding a 1024-word description of an image instead of the actual image. At the moment compute power isn't good enough to feed high-res pi…

> An embedding isn't conceptually that much different from feeding a 1024-word description of an image instead of the actual image. An embedding needs less words. You can embed individual words, phrases, like a whole prompt and longer paragraphs. You don't need 1024 words for a text embed. For example a famous library is called Sentence BERT (sbert). When you embed images on the other hand, you cut them up into littl…

> needs less words

Yes I'm aware of this, and work in ML -- the thing is embeddings are not designed for faithful image reconstruction, and aren't even trained that way. You can easily find two images that have substantially similar CLIP (or whatever) embeddings that are visually very different. If you query the LLM about that difference, the LLM wouldn't even have the information to differentiate answers for the two images if you only supply it with the embedding.

On the other hand, SDXL autoencoder latents passed into an LLM alongside the embedding might be a step up from just an image embedding, since they are designed for image reconstruction, but I don't have access to the compute or data resources to attempt training this.

Re: Vision language models are blind

#85

VLMs so far have never been good at counting objects or spatial relationships (e.g. the coffee is to the right of the microwave). There are ways to help the VLM out - Set of Marks [0] from Microsoft being the most prominent, which uses segmentation to outline and label sections of the image before sending to the VLM. Providing "speakable" labels to regions helps ground the visual abilities of VLMs and is why in this…

Vision models use CLiP or something similar, which has no conception of anything specific in the image. It sees embeddings which correlate similarly to text embeddings. Take an image then describe it 'there are birds sitting on a power line in front of a blue sky with some clouds', get the embeddings from that and the embeddings from that picture and line them up. If you ask if there are birds in it, it would know, but not how many, unless it was common to describe the number of birds sitting on things and it happened often enough that the number counted was the number in the image descriptions it trained on. If you want to count objects you want something like YOLO.

Re: Vision language models are blind

#86

Entertaining, but I think the conclusion is way off. > their vision is, at best, like that of a person with myopia seeing fine details as blurry is a crazy thing to write in an abstract. Did they try to probe that hypothesis at all? I could (well actually I can't) share some examples from my job of GPT-4v doing some pretty difficult fine-grained visual tasks that invalidate this. Personally, I rate this paper [1], wh…

>I could (well actually I can't) I like the idea that these models are so good at some sort of specific and secret bit of visual processing that things like “counting shapes” and “beating a coin toss for accuracy” shouldn’t be considered when evaluating them.

LLMs are bad at counting things just in general. It’s hard to say whether the failures here are vision based or just an inherent weakness of the language model.

Re: Vision language models are blind

#87

Entertaining, but I think the conclusion is way off. > their vision is, at best, like that of a person with myopia seeing fine details as blurry is a crazy thing to write in an abstract. Did they try to probe that hypothesis at all? I could (well actually I can't) share some examples from my job of GPT-4v doing some pretty difficult fine-grained visual tasks that invalidate this. Personally, I rate this paper [1], wh…

> Did they try to probe that hypothesis at all?

I think this is a communication issue and you're being a bit myopic in your interpretation. It is clearly an analogy meant for communication and is not an actual hypothesis. Sure, they could have used a better analogy and they could have done other tests, but the paper still counters quite common claims (from researchers) about VLMs.

> I could (well actually I can't) share some examples from my job of GPT-4v doing some pretty difficult fine-grained visual tasks that invalidate this.

I find it hard to believe that there is no example you can give. It surely doesn't have to be exactly your training data. If it is this good, surely you can create an example no problem. If you just don't want to, that's okay, but then don't say it.

But I have further questions. Do you have complicated prompting? Or any prompt engineering? It sure does matter how robust these models are to prompting. There's a huge difference between a model being able to accomplish a task and a model being able to perform a task in a non-very-specific environment. This is no different than something working in a tech demo and not in the hand of the user.

> But in practice, we aren't just making up tasks to trip up these models.

I see this sentiment quite often and it is baffling to me.

First off, these tasks are not clearly designed to trick these models. A model failing at a task is not suddenly "designed to trick a model." Its common with the river crossing puzzles where they're rewritten to be like "all animals can fit in the boat." If that is "designed to trick a model", then the model must be a stochastic parrot and not a generalist. It is very important that we test things where we do know the answer to because, unfortunately, we're not clairvoyant and can't test questions we don't know the answer to. Which is the common case in the real world usage.

Second, so what if a test was designed to trick up a model? Shouldn't we be determining when and where models fail? Is that not a critical question in understanding how to use them properly? This seems doubly important if they are tasks that humans don't have challenges with them.

> They can be very performant on some tasks and the authors have not presented any real evidence about these two modes.

I don't think people are claiming that large models can't be performant on some tasks. If they are, they're rejecting trivially verifiable reality. But not every criticism and has to also contain positive points. There's plenty of papers and a lot of hype already doing that. And if we're going to be critical of anything, shouldn't it be that the companies creating these models -- selling them, and even charging researchers to perform these types of experiments that the can and are used to improve their products -- should be much more clear about the limitations of their models? If we need balance, then I think there's bigger fish to fry than Auburn and Alberta Universities.

Re: Vision language models are blind

#88
post #9

Earlier quoted context omitted.

I don't see how this is "embarrassing" in the slightest. These models are not human brains, and the fact that people equate them with human brains is an embarrassing failure of the humans more than anything about the models. It's entirely unsurprising that there are numerous cases that these models can't handle that are "obvious to humans." Machine learning has had this property since its invention and it's a classic…

These models are marketed as being able to guide the blind or tutoring children using direct camera access. Promoting those use cases and models failing in these ways is irresponsible. So, yeah, maybe the models are not embarrasing but the hype definitely is.

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Re: Vision language models are blind

#90

My guess is that the systems are running image recognition models, and maybe OCR on images, and then just piping that data as tokens into an LLM. So you are only ever going to get results as good as existing images models with the results filtered through an LLM. To me, this is only interesting if compared with results of image recognition models that can already answer these types of questions (if they even exist, I…

> My guess is that the systems are running image recognition models

Your guess is incorrect. Look up CLIP, BLIP, and SigLip for an idea of how they work.

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