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Search - "autoencoder"
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Holy duck, I lost two days on a convolutional autoencoder splitted in two separate neural networks to encode and decode separately, it reconstruction had some strange behaviours. I was giving as input an image and then saving the encoded compressed representation in a new image, in this way I could decode it with the decoder whenever I want saving space.
How much retarded am I?
The internal layer's weights hadn't constraints so in learning phase the convolutional filters can contain any number, positive > 255 or even negative and I cannot save it in a new image as they are so they were clipped automatically between 0 and 255 with an huge information loss.
It's so frustrating when you rewrite the code in any possible way, you obtain the same wrong result and then you realize that was a borderline behaviour of a third part library.undefined convolution dimensionality reduction rbg autoencoder machine learning 255 neural networks image processing1 -
Heres some research into a new LLM architecture I recently built and have had actual success with.
The idea is simple, you do the standard thing of generating random vectors for your dictionary of tokens, we'll call these numbers your 'weights'. Then, for whatever sentence you want to use as input, you generate a context embedding by looking up those tokens, and putting them into a list.
Next, you do the same for the output you want to map to, lets call it the decoder embedding.
You then loop, and generate a 'noise embedding', for each vector or individual token in the context embedding, you then subtract that token's noise value from that token's embedding value or specific weight.
You find the weight index in the weight dictionary (one entry per word or token in your token dictionary) thats closest to this embedding. You use a version of cuckoo hashing where similar values are stored near each other, and the canonical weight values are actually the key of each key:value pair in your token dictionary. When doing this you align all random numbered keys in the dictionary (a uniform sample from 0 to 1), and look at hamming distance between the context embedding+noise embedding (called the encoder embedding) versus the canonical keys, with each digit from left to right being penalized by some factor f (because numbers further left are larger magnitudes), and then penalize or reward based on the numeric closeness of any given individual digit of the encoder embedding at the same index of any given weight i.
You then substitute the canonical weight in place of this encoder embedding, look up that weights index in my earliest version, and then use that index to lookup the word|token in the token dictionary and compare it to the word at the current index of the training output to match against.
Of course by switching to the hash version the lookup is significantly faster, but I digress.
That introduces a problem.
If each input token matches one output token how do we get variable length outputs, how do we do n-to-m mappings of input and output?
One of the things I explored was using pseudo-markovian processes, where theres one node, A, with two links to itself, B, and C.
B is a transition matrix, and A holds its own state. At any given timestep, A may use either the default transition matrix (training data encoder embeddings) with B, or it may generate new ones, using C and a context window of A's prior states.
C can be used to modify A, or it can be used to as a noise embedding to modify B.
A can take on the state of both A and C or A and B. In fact we do both, and measure which is closest to the correct output during training.
What this *doesn't* do is give us variable length encodings or decodings.
So I thought a while and said, if we're using noise embeddings, why can't we use multiple?
And if we're doing multiple, what if we used a middle layer, lets call it the 'key', and took its mean
over *many* training examples, and used it to map from the variance of an input (query) to the variance and mean of
a training or inference output (value).
But how does that tell us when to stop or continue generating tokens for the output?
Posted on pastebin if you want to read the whole thing (DR wouldn't post for some reason).
In any case I wasn't sure if I was dreaming or if I was off in left field, so I went and built the damn thing, the autoencoder part, wasn't even sure I could, but I did, and it just works. I'm still scratching my head.
https://pastebin.com/xAHRhmfH33 -
So I realized if done correctly, an autoencoder is really just a bootleg token dictionary.
If we take some input, and pass it through a custom hashfunction that strictly produces hashes with only digits as output, then we can train a network, store the weights and biases, and then train a decoder on top of that.
Using random drop out on the input-output pairs, we can do distillation of the weights and biases to find subgraphs that further condense this embedding.
Why have a token dictionary at all?10