Use multiple transformer layer in the same cross-attn blocks. (#653)

* Use multiple transformer layer in the same cross-attn blocks.

* Make the context contiguous if required.
This commit is contained in:
Laurent Mazare
2023-08-29 11:13:43 +01:00
committed by GitHub
parent d0a330448d
commit 62ef494dc1
4 changed files with 43 additions and 22 deletions

View File

@ -12,7 +12,9 @@ use candle_nn::Module;
#[derive(Debug, Clone, Copy)]
pub struct BlockConfig {
pub out_channels: usize,
pub use_cross_attn: bool,
/// When `None` no cross-attn is used, when `Some(d)` then cross-attn is used and `d` is the
/// number of transformer blocks to be used.
pub use_cross_attn: Option<usize>,
pub attention_head_dim: usize,
}
@ -41,22 +43,22 @@ impl Default for UNet2DConditionModelConfig {
blocks: vec![
BlockConfig {
out_channels: 320,
use_cross_attn: true,
use_cross_attn: Some(1),
attention_head_dim: 8,
},
BlockConfig {
out_channels: 640,
use_cross_attn: true,
use_cross_attn: Some(1),
attention_head_dim: 8,
},
BlockConfig {
out_channels: 1280,
use_cross_attn: true,
use_cross_attn: Some(1),
attention_head_dim: 8,
},
BlockConfig {
out_channels: 1280,
use_cross_attn: false,
use_cross_attn: None,
attention_head_dim: 8,
},
],
@ -149,13 +151,14 @@ impl UNet2DConditionModel {
downsample_padding: config.downsample_padding,
..Default::default()
};
if use_cross_attn {
if let Some(transformer_layers_per_block) = use_cross_attn {
let config = CrossAttnDownBlock2DConfig {
downblock: db_cfg,
attn_num_head_channels: attention_head_dim,
cross_attention_dim: config.cross_attention_dim,
sliced_attention_size,
use_linear_projection: config.use_linear_projection,
transformer_layers_per_block,
};
let block = CrossAttnDownBlock2D::new(
vs_db.pp(&i.to_string()),
@ -179,6 +182,11 @@ impl UNet2DConditionModel {
})
.collect::<Result<Vec<_>>>()?;
// https://github.com/huggingface/diffusers/blob/a76f2ad538e73b34d5fe7be08c8eb8ab38c7e90c/src/diffusers/models/unet_2d_condition.py#L462
let mid_transformer_layers_per_block = match config.blocks.last() {
None => 1,
Some(block) => block.use_cross_attn.unwrap_or(1),
};
let mid_cfg = UNetMidBlock2DCrossAttnConfig {
resnet_eps: config.norm_eps,
output_scale_factor: config.mid_block_scale_factor,
@ -186,8 +194,10 @@ impl UNet2DConditionModel {
attn_num_head_channels: bl_attention_head_dim,
resnet_groups: Some(config.norm_num_groups),
use_linear_projection: config.use_linear_projection,
transformer_layers_per_block: mid_transformer_layers_per_block,
..Default::default()
};
let mid_block = UNetMidBlock2DCrossAttn::new(
vs.pp("mid_block"),
bl_channels,
@ -231,13 +241,14 @@ impl UNet2DConditionModel {
add_upsample: i < n_blocks - 1,
..Default::default()
};
if use_cross_attn {
if let Some(transformer_layers_per_block) = use_cross_attn {
let config = CrossAttnUpBlock2DConfig {
upblock: ub_cfg,
attn_num_head_channels: attention_head_dim,
cross_attention_dim: config.cross_attention_dim,
sliced_attention_size,
use_linear_projection: config.use_linear_projection,
transformer_layers_per_block,
};
let block = CrossAttnUpBlock2D::new(
vs_ub.pp(&i.to_string()),