docs: Rework MIEB docs

docs/mieb.md

@@ -0,0 +1,116 @@
+# Welcome to MIEB! 👋
+
+The Massive Image Embedding Benchmark (MIEB) is an image extension of [MTEB](https://arxiv.org/abs/2210.07316) to cover embedding tasks for image-text tasks. 
+
+## 🌱 Background
+
+MIEB intends to extend MTEB and MMTEB to cover image representation learning and image-text alignment tasks. 
+
+## 🪴 Contributing to MIEB
+
+The FIRST step is to _always_ create an issue in the MTEB repo (this one), and add the `mieb` label. PRs without issues will not be accepted. 
+
+There are a few ways for anyone to contribute to MIEB:
+
+  1. Add a dataset as an existing task type. This means that the `AbsTask` already exists, e.g. `AbsTaskImageClassification`, and the effort is solely in adding an instance of it. 
+  2.  Add a model. This could mean either: a) The model wrapper, e.g. `OpenCLIPWrapper`, already exists, and the effort is solely in adding a filled out `ModelMeta` object, and/or b) Add a new model wrapper.
+  3. Add a new task type. This means that the existing task types do not cover this new task. An accompanying evaluator should also be implemented.
+
+Let's go through an example.
+
+## Example
+
+Here is an example implementing a zero-shot image classification from scratch. Let's say we wish to implement CIFAR10 as a task and evaluate an OpenCLIP model on it. 
+
+To solve this task, we need to encode the `images`, encode the `class label candidates with prompts` (e.g. "this is a dog pic", "this is a cat pic"), and compare them by calculating similarity, and then argmax out the class prediction for each image. We begin by implementing a model wrapper. 
+
+### Model Wrapper
+See the [`ImageEncoder` class](https://github.com/embeddings-benchmark/mteb/blob/mieb/mteb/encoder_interface.py) for more details. The model class implements `get_text_embeddings`, `get_image_embeddings`, and `calculate_probs` methods. 
+As an example,  [`OpenCLIPWrapper`](https://github.com/embeddings-benchmark/mteb/blob/mieb/mteb/models/openclip_models.py) is first implemented, with metadata defined below.
+```python
+class OpenCLIPWrapper:
+    ...
+```
+See also [adding a model](adding_a_model.md) for reference.
+
+### X Evaluator
+With the model, [ZeroshotClassificationEvaluator](https://github.com/embeddings-benchmark/mteb/blob/mieb/mteb/evaluation/evaluators/Image/ZeroshotClassificationEvaluator.py) is implemented here. This defines how the model are used to do zero-shot classification and get back results on desired metrics.
+```python
+class ZeroshotClassificationEvaluator(Evaluator):
+    def __init__(self, ...):
+        ...
+    def __call__(self, model: Encoder, *, encode_kwargs: dict[str, Any] = {}):
+        """Get embeddings and calculate scores."""
+        ...
+```
+
+### AbsTask X
+With the evaluator, [AbsTaskZeroshotClassification](https://github.com/embeddings-benchmark/mteb/blob/mieb/mteb/abstasks/Image/AbsTaskZeroshotClassification.py) is defined, operating on the dataset, calling the defined Evaluator, and gives out results.
+```python
+class AbsTaskZeroshotClassification(AbsTask):
+    ...
+```
+
+
+### Dataset class
+With all these, we can then define the dataset. [CIFAR10](https://github.com/embeddings-benchmark/mteb/blob/mieb/mteb/tasks/Image/ZeroshotClassification/eng/CIFAR.py) is implemented like this, subclassing `AbsTaskZeroshotClassification`, and overwrite the `get_candidate_labels` function, which gives `["a photo of {label_name}"]` to be used in the evaluator.
+```python
+class CIFAR10ZeroShotClassification(AbsTaskZeroshotClassification):
+    metadata = TaskMetadata(...)
+
+    def get_candidate_labels(self) -> list[str]:
+        ...
+```
+See also [adding a dataset](adding_a_dataset.md) for reference.
+
+### Putting them all together
+With all these, we can then 
+```python
+import mteb
+
+model_name = "laion/CLIP-ViT-L-14-laion2B-s32B-b82K"
+model = mteb.get_model(model_name=model_name)
+
+tasks = mteb.get_tasks(tasks=["CIFAR10ZeroShot"])
+evaluation = mteb.MTEB(tasks=tasks)
+results = evaluation.run(model)
+```
+
+By default, results will be under `results/laion__CLIP-ViT-L-14-laion2B-s32B-b82K/REVISION/CIFAR10ZeroShot.json`. Sometimes metrics can be a bit different than what the original paper claimed. This might be due to the resolution/layout difference of images in the remake of the dataset.
+
+
+## Specific Model running Instructions
+
+Some models require some specific steps before running. Those are collected here.
+
+<details>
+    <summary> Vista </summary>
+
+    ## set up VISTA 
+
+    ```
+    git clone https://github.com/FlagOpen/FlagEmbedding.git
+    cd FlagEmbedding/research/visual_bge
+    pip install -e .
+    pip install torchvision timm einops ftfy
+    ```
+    back to the root folder of mteb; download the vision tower for bge-base
+    ```
+    cd ..
+    wget https://huggingface.co/BAAI/bge-visualized/resolve/main/Visualized_base_en_v1.5.pth?download=true
+    ```
+    rename it to `visualized_base_en_V1.5.pth`
+    ```
+    mv Visualized_base_en_v1.5.pth?download=true visualized_base_en_V1.5.pth
+    ```
+    download the vision tower for bge-m3
+    ```
+    wget https://huggingface.co/BAAI/bge-visualized/resolve/main/Visualized_m3.pth?download=true
+    ```
+    rename it to `visualized_m3.pth`
+    ```
+    mv Visualized_m3.pth?download=true visualized_m3.pth
+    ```
+
+
+</details>

tests/test_tasks/test_all_abstasks.py

@@ -93,7 +93,14 @@ async def check_datasets_are_available_on_hf(tasks):
 def test_dataset_availability():
     """Checks if the datasets are available on Hugging Face using both their name and revision."""
     tasks = MTEB().tasks_cls
-    tasks = [t for t in tasks if t.metadata.name not in ALL_MOCK_TASKS]
+    tasks = [
+        t
+        for t in tasks
+        if t.metadata.name not in MOCK_TASK_TEST_GRID_AS_STRING
+        if t.metadata.name not in MOCK_MIEB_TASK_GRID_AS_STRING
+        and t.metadata.name
+        != "AfriSentiLangClassification"  # HOTFIX: Issue#1777. Remove this line when issue is resolved.
+    ]
     asyncio.run(check_datasets_are_available_on_hf(tasks))