gemini-torch 0.0.7

Gemini - Pytorch

Gemini

The open source implementation of Gemini, the model that will "eclipse ChatGPT", it seems to work by directly taking in all modalities all at once into a transformer with special decoders for text or img generation!

The input sequences for Gemini consist of texts, audio, images, and videos. These inputs are transformed into tokens, which are then processed by a transformer. Subsequently, conditional decoding takes place to generate image outputs.

Interestingly, the architecture of Gemini bears resemblance to Fuyu's architecture but is expanded to encompass multiple modalities. Instead of utilizing a visual transformer (vit) encoder, Gemini simply feeds image embeddings directly into the transformer.

For Gemini, the token inputs will likely be indicated by special modality tokens such as [IMG], , [AUDIO], or . Codi, a component of Gemini, also employs conditional generation and makes use of the tokenized outputs.

To implement this model effectively, I intend to initially focus on the image embeddings to ensure their smooth integration. Subsequently, I will proceed with incorporating audio embeddings and then video embeddings.

Install

pip3 install gemini-torch

Usage

Gemini Transformer Usage

• Base transformer
• Multi Grouped Query Attn / flash attn
• rope
• alibi
• xpos
• qk norm
• no pos embeds
• kv cache

import torch 
from gemini_torch import Gemini

# Initialize the model
model = Gemini(
    num_tokens=50432,
    max_seq_len=8192,
    dim=2560,
    depth=32,
    dim_head=128,
    heads=24,
    use_abs_pos_emb=False,
    alibi_pos_bias=True,
    alibi_num_heads=12,
    rotary_xpos=True,
    attn_flash=True,
    attn_kv_heads=2,
    qk_norm=True,
    attn_qk_norm=True,
    attn_qk_norm_dim_scale=True,
)

# Initialize the text random tokens
x = torch.randint(0, 50432, (1, 8192))

# Apply model to x
y = model(x)

# Print logits
print(y)

---

Multi-Modal with Imgs + Audio

• Img processing through a specially crafted module that takes in img -> patches it -> then reshapes to the shape of the text tensors, [B, seqlen, dim] -> align with text tokens

import torch
from gemini_torch.model import Gemini

# Initialize model
model = Gemini(
    num_tokens=50432,
    max_seq_len=8192,
    dim=2560,
    depth=32,
    dim_head=128,
    heads=24,
    use_abs_pos_emb=False,
    alibi_pos_bias=True,
    alibi_num_heads=12,
    rotary_xpos=True,
    attn_flash=True,
    attn_kv_heads=2,
    qk_norm=True,
    attn_qk_norm=True,
    attn_qk_norm_dim_scale=True,
)

# Text shape: [batch, seq_len, dim]
text = torch.randint(0, 50432, (1, 8192))

# Img shape: [batch, channels, height, width]
img = torch.randn(1, 3, 256, 256)

# Audio shape: [batch, audio_seq_len, dim]
audio = torch.randn(1, 128)

# Apply model to text and img
y = model(text, img, audio)

# Output shape: [batch, seq_len, dim]
print(y.shape)

---

Tokenizer

• We're using the same tokenizer as LLAMA with special tokens denoting the beginning and end of the multi modality tokens.
• Does not fully process img, audio, or videos now we need help on that

from gemini_torch.tokenizer import MultimodalSentencePieceTokenizer

# Example usage
tokenizer_name = "hf-internal-testing/llama-tokenizer"
tokenizer = MultimodalSentencePieceTokenizer(tokenizer_name=tokenizer_name)

# Encoding and decoding examples
encoded_audio = tokenizer.encode("Audio description", modality="audio")
decoded_audio = tokenizer.decode(encoded_audio)

print("Encoded audio:", encoded_audio)
print("Decoded audio:", decoded_audio)

ImgToTransformer

• takes in img -> patches -> reshapes to [B, SEQLEN, Dim] to align with transformer

import torch
from gemini_torch.utils import ImgToTransformer

# Example usage
num_patches = 16
patch_size = 16
transformer_dim = 512
img_channels = 3
seq_len = 50000
reduced_dim = 256  # Reduced dimension after dimensionality reduction

model = ImgToTransformer(
    num_patches, patch_size, transformer_dim, img_channels, seq_len, reduced_dim
)

# Dummy image input [BATCH, CHANNELS, HEIGHT, WIDTH]
dummy_img = torch.randn(1, 3, 64, 64)  # Batch size of 1, 64x64 RGB image

# Forward pass
seq_space_output = model(dummy_img)
print(seq_space_output.shape)  # Expected shape: [1, 50000, 256]

AudioToLangEmbedding

• Transforms audio into the same shape as text tensors.

import torch 
from gemini_torch.utils import AudioToLangEmbedding

# Example usage
audio_seq_len = 32000  # Input audio sequence length
seqlen = 512  # Sequence length to align with the language transformer
dim = 512  # Embedding dimension

model = AudioToLangEmbedding(audio_seq_len, seqlen, dim)
audio_input = torch.randn(1, audio_seq_len)  # Example input tensor
output = model(audio_input)

print("Output shape:", output.shape)  # Should be [1, 512, 512]

References

• Combine Reinforcment learning with modular pretrained transformer, multi-modal capabilities, image, audio,
• self improving mechanisms like robocat
• PPO? or MPO
• get good at backtracking and exploring alternative paths
• speculative decoding
• Algorithm of Thoughts
• RLHF
• Gemini Report
• Gemini Landing Page

Todo

• Implement the img feature embedder and align imgs with text and pass into transformer
• Implement the audio processing by making an audio processor that intakes in audio embeddings and reshapes it to match language embeddings dimension shape [B, SEQLEN, Dim]
• Do the same for video