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Vision language models are blind

vlmsareblind.github.io

121–130 of 202 posts

Re: Vision language models are blind

#121
post #106

Earlier quoted context omitted.

There are quite a few "ai apologists" in the comments but I think the title is fair when these models are marketed towards low vision people ("Be my eyes" https://www.youtube.com/watch?v=Zq710AKC1gg ) as the equivalent to human vision. These models are implied to be human level equivalents when they are not. This paper demonstrates that there are still some major gaps where simple problems confound the models in unex…

I disagree. I think the title, abstract, and conclusion not only misrepresents the state of the models but it misrepresents Thier own findings. They have identified a class of problems that the models perform poorly at and have given a good description of the failure. They portray this as a representative example of the behaviour in general. This has not been shown and is probably not true. I don't think that models…

I think the conclusion of the paper is far more mundane. It's curious that VLM can recognize complex novel objects in a trained category, but cannot perform basic visual tasks that human toddlers can perform (e.g. recognizing when two lines intersect or when two circles overlap). Nevertheless I'm sure these models can explain in great detail what intersecting lines are, and even what they look like. So while LLMs might have image processing capabilities, they clearly do not see the way humans see. That, I think, would be a more apt title for their abstract.

Re: Vision language models are blind

#122
post #28

I tought some Computational Geometry courses and efficiently computing the intersections of N line segments is not as straightforward as you might initially think. Since somewhere some computation must be done to recognize this and LLMs are not specifically trained for this task, it's not suprising they struggle. In general, basic geometry seems under-explored by learning.

> Since somewhere some computation must be done to recognize this

Humans don't have a "compute intersections" ability (other than a few who have learned it laboriously through algebra), we have a "see things and count them" mechanism. We aren't visually taking lines in a planar space and determining where they cross. We know what an intersection looks like, we see one, increment a counter, and find the next one. If it's less than around five, we do this all at once. Otherwise we literally count, sometimes in small groups, sometimes one at a time.

Re: Vision language models are blind

#124
This says to me that there are huge opportunities for improvement in providing vision modules for LLMs. Human minds aren't made of just one kind of thing: we have all sorts of hacky modular capabilities – there's no reason to think that a future AGI wouldn't also.

Re: Vision language models are blind

#125
post #52

I don't like this paper for the following reasons: - The language is unnecessarily scathing - They repeatedly show data where the models are getting things right 70, 80, 90% of the time, and then show a list of what they call "qualitative samples" (what does "qualitative" mean? "cherry-picked"?) which look very bad. But it got the answer right 70/80/90% of the time! That's hardly "blind"... - Various of the tasks hin…

I'm also confused about some of the figures' captions, which don't seem to match the results:

- "Only Sonnet-3.5 can count the squares in a majority of the images", but Sonnet-3, Gemini-1.5 and Sonnet-3.5 all have accuracy of >50%

- "Sonnet-3.5 tends to conservatively answer "No" regardless of the actual distance between the two circles.", but it somehow gets 91% accuracy? That doesn't sound like it tends to answer "No" regardless of distance.

Re: Vision language models are blind

#126
post #52

I don't like this paper for the following reasons: - The language is unnecessarily scathing - They repeatedly show data where the models are getting things right 70, 80, 90% of the time, and then show a list of what they call "qualitative samples" (what does "qualitative" mean? "cherry-picked"?) which look very bad. But it got the answer right 70/80/90% of the time! That's hardly "blind"... - Various of the tasks hin…

I am not sure where their experimental data came from. I tested it on GPT-4o using the prompt and images they provided, and the success rate was quite high, with significant differences from the results they provided.

Re: Vision language models are blind

#127

Earlier quoted context omitted.

Exactly... I've found GPT-4o to be good at OCR for instance... doesn't seem "blind" to me.

You don't really need a LLM for OCR. Hell, I suppose they just run a python script in its VM and rephrase the output. At least that's what I would do. Perhaps the script would be a "specialist model" in a sense.

It's not that you need an LLM for OCR but the fact that an LLM can do OCR (and handwriting recognition which is much harder) despite not being made specifically for that purpose is indicative of something. The jump from knowing "this is a picture of a paper with writing on it" like what you get with CLIP to being able to reproduce what's on the paper is, to me, close enough to seeing that the difference isn't meaningful anymore.

Re: Vision language models are blind

#128
Vision Transformers do a shocking amount of compression in the tokenizer. In the [Chameleon paper](https://arxiv.org/pdf/2405.09818) they say the tokenizer "encodes a 512 × 512 image into 1024 discrete tokens from a codebook of size 8192". That's 256 pixels per token (512 * 512 / 1024). If we assume that a pixel is 24 bits (3x 8 bit channels), this implies that they've compressed 256 * 24 = 6144 bits into 13 = (log2(8192)). [An Image is Worth 32 Tokens for Reconstruction and Generation](https://yucornetto.github.io/projects/titok.html) pushes this even further. If these models work similarly, it's no wonder they struggle with some vision tasks.

Re: Vision language models are blind

#129

Earlier quoted context omitted.

> 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) sh…

> 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. I don't know, words have meanings. If that's a communication issue, it's on part of the authors. To me, this wording in a what is supposed to be a research paper abstract clearly suggests the insufficient resolution as the cause. How else shoul…

> I don't know, words have meanings.

That's quite true. Words mean exactly what people agree upon them meaning. Which does not require everyone, or else slang wouldn't exist. Nor the dictionary, which significantly lags. Regardless, I do not think this is even an unusual use of the word, though I agree the mention of myopia is. The usage makes sense if you consider that both myopic and resolution have more than a singular meaning.

  Myopic:
  lacking in foresight or __discernment__ : narrow in perspective and without concern for broader implications

  Resolution:
  the process or capability of making distinguishable the individual parts of an object, closely adjacent optical images, or sources of light
I agree that there are far better ways to communicate. But my main gripe is that they said it was "their hypothesis." If reading the abstract as a whole, I find it an odd conclusion to come to. It doesn't pair with the words that follow with blind guessing (and I am not trying to defend the abstract. It is a bad abstract). But if you read the intro and look at the context of their landing page, I find it quite difficult to come to this conclusion. It is poorly written, but it is still not hard to decode the key concepts the authors are trying to convey.

I feel the need to reiterate that language has 3 key aspects to it: the concept attempted to be conveyed, the words that concept is lossy encoded into, and the lossy decoding of the person interpreting it. Communication doesn't work by you reading/listening to words and looking up those words in a dictionary. Communication is a problem where you use words (context/body language/symbols/etc) to decrease the noise and get the reciever to reasonably decode your intended message. And unfortunately we're in a global world and many different factors, such as culture, greatly affect how one encodes and/or decodes language. It only becomes more important to recognize the fuzziness around language here. Being more strict and leaning into the database view of language only leads to more errors.

> But the low resolution is clearly not the issue here, and the authors don't actually talk about it in the paper.

Because they didn't claim that image size and sharpness was an issue. They claimed the VLM cannot resolve the images "as if" they were blurry. Determining what the VLM actually "sees" is quite challenging. And I'll mention that arguably they did test some factors that relate to blurriness. Which is why I'm willing to overlook the poor analogy.

> I actually lazily tried two of authors' examples in a less performant VLM (CogVLM), and was surprised it passed those

I'm not. Depending on the examples you pulled, 2 random ones passing isn't unlikely given the results.

Something I generally do not like about these types of papers is that they often do not consider augmentations. Since these models tend to be quite sensitive to both the text (prompt) inputs and image inputs. This is quite common in generators in general. Even the way you load in and scale an image can have significant performance differences. I've seen significant differences in simple things like loading an image from numpy, PIL, tensorflow, or torch have different results. But I have to hand it to these authors, they looked at some of this. In the appendix they go through with confusion matrices and look at the factors that determine misses. They could have gone deeper and tried other things, but it is a more than reasonable amount of work for a paper.

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