ollama/model/models/qwen25vl/model_vision.go

248 lines
8.5 KiB
Go

package qwen25vl
import (
"math"
"github.com/ollama/ollama/fs"
"github.com/ollama/ollama/ml"
"github.com/ollama/ollama/ml/nn"
)
var batchSize int = 1
// VisionSelfAttention implements self-attention for the Qwen vision model
type VisionSelfAttention struct {
Query *nn.Linear `gguf:"attn_q"`
Key *nn.Linear `gguf:"attn_k"`
Value *nn.Linear `gguf:"attn_v"`
Output *nn.Linear `gguf:"attn_out"`
}
// Forward computes self-attention for the vision model
func (sa *VisionSelfAttention) Forward(ctx ml.Context, hiddenStates ml.Tensor, positionIDs ml.Tensor, opts *VisionModelOptions) ml.Tensor {
query := sa.Query.Forward(ctx, hiddenStates)
key := sa.Key.Forward(ctx, hiddenStates)
value := sa.Value.Forward(ctx, hiddenStates)
query = query.Reshape(ctx, opts.headDim, opts.numHeads, query.Dim(1), batchSize)
key = key.Reshape(ctx, opts.headDim, opts.numHeads, key.Dim(1), batchSize)
value = value.Reshape(ctx, opts.headDim, opts.numHeads, value.Dim(1), batchSize)
config := ml.RoPEConfig{
Dim: uint32(opts.headDim / 2),
Type: ml.RopeTypeMRoPE,
Base: opts.ropeTheta,
Scale: 1.0,
YarnConfig: ml.DefaultYarnConfig(128000),
}
query = query.RoPEMulti(
ctx,
positionIDs,
nil,
[4]int{opts.headDim / 4, opts.headDim / 4, opts.headDim / 4, opts.headDim / 4},
config,
)
key = key.RoPEMulti(
ctx,
positionIDs,
nil,
[4]int{opts.headDim / 4, opts.headDim / 4, opts.headDim / 4, opts.headDim / 4},
config,
)
// Scale factor for scaled dot-product attention
scale := 1.0 / math.Sqrt(float64(opts.headDim))
attention := nn.Attention(ctx, query, key, value, scale, nil)
attention = attention.Reshape(ctx, opts.hiddenSize, attention.Dim(2), batchSize)
return sa.Output.Forward(ctx, attention)
}
// VisionMLP implements the MLP for the Qwen vision model
type VisionMLP struct {
Gate *nn.Linear `gguf:"ffn_gate"`
Up *nn.Linear `gguf:"ffn_up"`
Down *nn.Linear `gguf:"ffn_down"`
}
// Forward computes the MLP for the vision model
func (mlp *VisionMLP) Forward(ctx ml.Context, hiddenStates ml.Tensor, opts *VisionModelOptions) ml.Tensor {
// Using GEGLU activation: (Gate * Up) * GELU(Gate)
gateOutput := mlp.Gate.Forward(ctx, hiddenStates)
upOutput := mlp.Up.Forward(ctx, hiddenStates)
hiddenStates = gateOutput.GELU(ctx).Mul(ctx, upOutput)
return mlp.Down.Forward(ctx, hiddenStates)
}
// VisionEncoderLayer implements an encoder layer for the Qwen vision model
type VisionEncoderLayer struct {
Norm1 *nn.RMSNorm `gguf:"ln1"`
Norm2 *nn.RMSNorm `gguf:"ln2"`
SelfAttention *VisionSelfAttention
MLP *VisionMLP
}
// Forward computes an encoder layer for the vision model
func (e *VisionEncoderLayer) Forward(ctx ml.Context, hiddenStates ml.Tensor, positionIDs ml.Tensor, opts *VisionModelOptions) ml.Tensor {
residual := hiddenStates
hiddenStates = e.Norm1.Forward(ctx, hiddenStates, opts.eps)
hiddenStates = e.SelfAttention.Forward(ctx, hiddenStates, positionIDs, opts)
hiddenStates = hiddenStates.Add(ctx, residual)
residual = hiddenStates
hiddenStates = e.Norm2.Forward(ctx, hiddenStates, opts.eps)
hiddenStates = e.MLP.Forward(ctx, hiddenStates, opts)
return hiddenStates.Add(ctx, residual)
}
// VisionModelOptions contains configuration options for the Qwen vision model
type VisionModelOptions struct {
hiddenSize int
numHeads int
headDim int
intermediateSize int
imageSize int
patchSize int
numChannels int
eps float32
ropeTheta float32
outHiddenSize int
}
type PatchEmbedding struct {
PatchConv0 *nn.Conv2D `gguf:"patch_embd_0"` // TODO: `gguf:"patch_embed_0"`
PatchConv1 *nn.Conv2D `gguf:"patch_embd_1"`
}
func (pe *PatchEmbedding) Forward(ctx ml.Context, pixelValues ml.Tensor, numChannels, embedDim, patchSize int) ml.Tensor {
temporalPatchSize := 2 // we have two temporal convolutions
numPatches := pixelValues.Shape()[1]
// Reshape the input tensor to match the expected dimensions
pixelValues = pixelValues.Reshape(ctx, patchSize*patchSize, temporalPatchSize, numChannels, numPatches)
// Permute the tensor to bring the temporal dimension to the front
pixelValues = pixelValues.Permute(ctx, 1, 0, 2, 3).Contiguous(ctx)
// Split the tensor into two parts for the two temporal convolutions
in0 := pixelValues.View(ctx, 0, 1, pixelValues.Stride(1), pixelValues.Dim(1), pixelValues.Stride(2), pixelValues.Dim(2), pixelValues.Stride(3), pixelValues.Dim(3)).Contiguous(ctx)
in0 = in0.Reshape(ctx, patchSize, patchSize, numChannels, numPatches)
in1 := pixelValues.View(ctx, pixelValues.Stride(0), 1, pixelValues.Stride(1), pixelValues.Dim(1), pixelValues.Stride(2), pixelValues.Dim(2), pixelValues.Stride(3), pixelValues.Dim(3)).Contiguous(ctx)
in1 = in1.Reshape(ctx, patchSize, patchSize, numChannels, numPatches)
s0, s1 := patchSize, patchSize // Use full stride
p0, p1 := 0, 0 // padding
d0, d1 := 1, 1 // dilation
out0 := pe.PatchConv0.Forward(ctx, in0, s0, s1, p0, p1, d0, d1)
out1 := pe.PatchConv1.Forward(ctx, in1, s0, s1, p0, p1, d0, d1)
// Add the outputs from the two temporal convolutions
out := out0.Add(ctx, out1)
// Reshape the output tensor to match the expected dimensions
return out.Reshape(ctx, embedDim, numPatches)
}
// VisionPatchMerger implements patch merging for the Qwen vision model
type VisionPatchMerger struct {
LNQ *nn.RMSNorm `gguf:"ln_q"`
MLP *nn.Linear `gguf:"mlp"`
}
// Forward computes patch merging for the vision model
func (pm *VisionPatchMerger) Forward(ctx ml.Context, x ml.Tensor, outDim, contextDim, spatialMergeSize int) ml.Tensor {
hiddenSize := contextDim * (spatialMergeSize * spatialMergeSize)
// Normalize and reshape
x = pm.LNQ.Forward(ctx, x, 1e-6)
x = x.Reshape(ctx, -1, hiddenSize)
// Apply MLP for merging
x = pm.MLP.Forward(ctx, x)
return x
}
// VisionModel implements the Qwen vision model
type VisionModel struct {
PatchEmbedding *PatchEmbedding
Layers []VisionEncoderLayer `gguf:"blk"`
PostLayerNorm *nn.LayerNorm `gguf:"post_ln"`
PatchMerger *VisionPatchMerger `gguf:"patch_merger"`
*VisionModelOptions
}
// Forward computes the vision model for an input tensor
func (m *VisionModel) Forward(ctx ml.Context, pixelValues ml.Tensor, grid *Grid) ml.Tensor {
// Calculate position IDs for 2D RoPE
numPatchesH := pixelValues.Dim(0) / m.patchSize
numPatchesW := pixelValues.Dim(1) / m.patchSize
numPatches := numPatchesH * numPatchesW
// Extract patch embeddings
hiddenStates := m.PatchEmbedding.Forward(
ctx,
pixelValues, // processed image tensor
m.numChannels, // number of channels, e.g., 3 for RGB
m.hiddenSize, // embedding size
m.patchSize, // patch size, e.g., 14
)
// Create position IDs - for Qwen2VL mRoPE we need 4 values per position
positions := make([]int32, numPatches*4)
for h := 0; h < numPatchesH; h++ {
for w := 0; w < numPatchesW; w++ {
idx := h*numPatchesW + w
// For each position, store both h and w coordinates twice
positions[idx*4] = int32(h) // y coordinate
positions[idx*4+1] = int32(w) // x coordinate
positions[idx*4+2] = int32(h) // y coordinate (repeated)
positions[idx*4+3] = int32(w) // x coordinate (repeated)
}
}
// Create the position IDs tensor with correct dimensions
positionIDs, err := ctx.Input().FromIntSlice(positions, numPatches*4)
if err != nil {
panic(err)
}
// Apply encoder layers
for _, layer := range m.Layers {
hiddenStates = layer.Forward(ctx, hiddenStates, positionIDs, m.VisionModelOptions)
}
hiddenStates = m.PostLayerNorm.Forward(ctx, hiddenStates, m.eps)
return hiddenStates
}
// newVisionModel creates a new instance of the Qwen vision model
func newVisionModel(c fs.Config) *VisionModel {
patchSize := int(c.Uint("vision.patch_size", 14))
hiddenSize := int(c.Uint("vision.embedding_length", 1280))
ropeTheta := c.Float("vision.rope_theta", 10000.0) // not set
outHiddenSize := int(c.Uint("vision.out_embedding_length", 0)) // not set
numHeads := int(c.Uint("vision.attention.head_count", 16))
return &VisionModel{
Layers: make([]VisionEncoderLayer, c.Uint("vision.block_count", 24)),
VisionModelOptions: &VisionModelOptions{
hiddenSize: hiddenSize,
numHeads: numHeads,
headDim: hiddenSize / numHeads,
intermediateSize: int(c.Uint("vision.feed_forward_length", 0)),
imageSize: int(c.Uint("vision.image_size", 560)),
patchSize: patchSize,
numChannels: int(c.Uint("vision.num_channels", 3)), // not set
eps: c.Float("vision.attention.layer_norm_epsilon", 1e-6),
ropeTheta: ropeTheta,
outHiddenSize: outHiddenSize,
},
}
}