Deprecate #36741 and map Causal to Conditional (#36917)

* deprecate the prev fix

* reword warning and update docs

* reword warning

* tests

* dont bloat `get_text_config()`
This commit is contained in:
Raushan Turganbay
2025-03-25 09:13:56 +01:00
committed by Arthur Zucker
parent e6ab93e702
commit d9ccb9adbb
4 changed files with 83 additions and 50 deletions

View File

@@ -105,59 +105,75 @@ inputs = processor.apply_chat_template(
add_generation_prompt=True,
).to(model.device)
output = model.generate(**inputs, max_new_tokens=50)
print(processor.decode(output[0], skip_special_tokens=True)[inputs.input_ids.shape[1]: ])
output = model.generate(**inputs, max_new_tokens=50, cache_implementation="static")
print(processor.decode(output[0], skip_special_tokens=True))
```
### Multi-image Inference
Use the [AttentionMaskVisualizer](https://github.com/huggingface/transformers/blob/beb9b5b02246b9b7ee81ddf938f93f44cfeaad19/src/transformers/utils/attention_visualizer.py#L139) to better understand what tokens the model can and cannot attend to.
```python
model_id = "google/gemma-3-4b-it"
model = Gemma3ForConditionalGeneration.from_pretrained(model_id, device_map="auto")
processor = AutoProcessor.from_pretrained(model_id, padding_side="left")
url_cow = "https://media.istockphoto.com/id/1192867753/photo/cow-in-berchida-beach-siniscola.jpg?s=612x612&w=0&k=20&c=v0hjjniwsMNfJSuKWZuIn8pssmD5h5bSN1peBd1CmH4="
url_stop = "https://www.ilankelman.org/stopsigns/australia.jpg"
messages = [
{
"role": "system",
"content": [
{"type": "text", "text": "You are a helpful assistant."}
]
},
{
"role": "user", "content": [
{"type": "image", "url": url_cow},
{"type": "image", "url": url_stop},
{"type": "text", "text": "Are these two images identical?"},
]
},
]
inputs = processor.apply_chat_template(
messages,
tokenize=True,
return_dict=True,
return_tensors="pt",
add_generation_prompt=True,
).to(model.device)
output = model.generate(**inputs, max_new_tokens=50)
print(processor.decode(output[0], skip_special_tokens=True)[inputs.input_ids.shape[1]: ])
```py
from transformers.utils.attention_visualizer import AttentionMaskVisualizer
visualizer = AttentionMaskVisualizer("google/gemma-3-4b-it")
visualizer("<img>What is shown in this image?")
```
### Text-only inference
## Notes
You can use the VLMs for text-only generation by omitting images in your input. However, you can also load the models in text-only mode as shown below. This will skip loading the vision tower and will save resources when you just need the LLM capabilities.
```python
from transformers import AutoTokenizer, Gemma3ForCausalLM
- Use [`Gemma3ForConditionalGeneration`] for image-and-text and image-only inputs.
- Gemma 3 supports multiple input images, but make sure the images are correctly batched before passing them to the processor. Each batch should be a list of one or more images.
model_id = "google/gemma-3-1b-it"
```py
url_cow = "https://media.istockphoto.com/id/1192867753/photo/cow-in-berchida-beach-siniscola.jpg?s=612x612&w=0&k=20&c=v0hjjniwsMNfJSuKWZuIn8pssmD5h5bSN1peBd1CmH4="
url_cat = "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/pipeline-cat-chonk.jpeg"
tokenizer = AutoTokenizer.from_pretrained(model_id)
model = Gemma3ForCausalLM.from_pretrained(model_id, device_map="auto")
messages =[
{
"role": "system",
"content": [
{"type": "text", "text": "You are a helpful assistant."}
]
},
{
"role": "user",
"content": [
{"type": "image", "url": url_cow},
{"type": "image", "url": url_cat},
{"type": "text", "text": "Which image is cuter?"},
]
},
]
```
- Text passed to the processor should have a `<start_of_image>` token wherever an image should be inserted.
- The processor has its own [`~ProcessorMixin.apply_chat_template`] method to convert chat messages to model inputs.
- By default, images aren't cropped and only the base image is forwarded to the model. In high resolution images or images with non-square aspect ratios, artifacts can result because the vision encoder uses a fixed resolution of 896x896. To prevent these artifacts and improve performance during inference, set `do_pan_and_scan=True` to crop the image into multiple smaller patches and concatenate them with the base image embedding. You can disable pan and scan for faster inference.
input_ids = tokenizer("Write me a poem about Machine Learning.", return_tensors="pt").to(model.device)
```diff
inputs = processor.apply_chat_template(
messages,
tokenize=True,
return_dict=True,
return_tensors="pt",
add_generation_prompt=True,
+ do_pan_and_scan=True,
).to("cuda")
```
- For Gemma-3 1B checkpoint trained in text-only mode, use [`AutoModelForCausalLM`] instead.
```py
import torch
from transformers import AutoModelForCausalLM, AutoTokenizer
tokenizer = AutoTokenizer.from_pretrained(
"google/gemma-3-1b-pt",
)
model = AutoModelForCausalLM.from_pretrained(
"google/gemma-3-1b-pt",
torch_dtype=torch.bfloat16,
device_map="auto",
attn_implementation="sdpa"
)
input_ids = tokenizer("Plants create energy through a process known as", return_tensors="pt").to("cuda")
outputs = model.generate(**input_ids, max_new_tokens=100)
text = tokenizer.batch_decode(outputs, skip_special_tokens=True)