You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

188 lines
9.9 KiB

<img width="1024" src="https://github.com/ultralytics/assets/raw/main/yolov8/banner-integrations.png">
YOLOv8 **predict mode** can generate predictions for various tasks, returning either a list of `Results` objects or a
memory-efficient generator of `Results` objects when using the streaming mode. Enable streaming mode by
passing `stream=True` in the predictor's call method.
!!! example "Predict"
=== "Return a list with `Stream=False`"
```python
inputs = [img, img] # list of numpy arrays
results = model(inputs) # list of Results objects
for result in results:
boxes = result.boxes # Boxes object for bbox outputs
masks = result.masks # Masks object for segmentation masks outputs
probs = result.probs # Class probabilities for classification outputs
```
=== "Return a list with `Stream=True`"
```python
inputs = [img, img] # list of numpy arrays
results = model(inputs, stream=True) # generator of Results objects
for result in results:
boxes = result.boxes # Boxes object for bbox outputs
masks = result.masks # Masks object for segmentation masks outputs
probs = result.probs # Class probabilities for classification outputs
```
!!! tip "Tip"
Streaming mode with `stream=True` should be used for long videos or large predict sources, otherwise results will accumuate in memory and will eventually cause out-of-memory errors.
## Sources
YOLOv8 can accept various input sources, as shown in the table below. This includes images, URLs, PIL images, OpenCV,
numpy arrays, torch tensors, CSV files, videos, directories, globs, YouTube videos, and streams. The table indicates
whether each source can be used in streaming mode with `stream=True` ✅ and an example argument for each source.
| source | model(arg) | type | notes |
|-------------|--------------------------------------------|----------------|------------------|
| image | `'im.jpg'` | `str`, `Path` | |
| URL | `'https://ultralytics.com/images/bus.jpg'` | `str` | |
| screenshot | `'screen'` | `str` | |
| PIL | `Image.open('im.jpg')` | `PIL.Image` | HWC, RGB |
| OpenCV | `cv2.imread('im.jpg')[:,:,::-1]` | `np.ndarray` | HWC, BGR to RGB |
| numpy | `np.zeros((640,1280,3))` | `np.ndarray` | HWC |
| torch | `torch.zeros(16,3,320,640)` | `torch.Tensor` | BCHW, RGB |
| CSV | `'sources.csv'` | `str`, `Path` | RTSP, RTMP, HTTP |
| video ✅ | `'vid.mp4'` | `str`, `Path` | |
| directory ✅ | `'path/'` | `str`, `Path` | |
| glob ✅ | `'path/*.jpg'` | `str` | Use `*` operator |
| YouTube ✅ | `'https://youtu.be/Zgi9g1ksQHc'` | `str` | |
| stream ✅ | `'rtsp://example.com/media.mp4'` | `str` | RTSP, RTMP, HTTP |
## Image and Video Formats
YOLOv8 supports various image and video formats, as specified
in [yolo/data/utils.py](https://github.com/ultralytics/ultralytics/blob/main/ultralytics/yolo/data/utils.py). See the
tables below for the valid suffixes and example predict commands.
### Image Suffixes
| Image Suffixes | Example Predict Command | Reference |
|----------------|----------------------------------|-------------------------------------------------------------------------------|
| .bmp | `yolo predict source=image.bmp` | [Microsoft BMP File Format](https://en.wikipedia.org/wiki/BMP_file_format) |
| .dng | `yolo predict source=image.dng` | [Adobe DNG](https://www.adobe.com/products/photoshop/extend.displayTab2.html) |
| .jpeg | `yolo predict source=image.jpeg` | [JPEG](https://en.wikipedia.org/wiki/JPEG) |
| .jpg | `yolo predict source=image.jpg` | [JPEG](https://en.wikipedia.org/wiki/JPEG) |
| .mpo | `yolo predict source=image.mpo` | [Multi Picture Object](https://fileinfo.com/extension/mpo) |
| .png | `yolo predict source=image.png` | [Portable Network Graphics](https://en.wikipedia.org/wiki/PNG) |
| .tif | `yolo predict source=image.tif` | [Tag Image File Format](https://en.wikipedia.org/wiki/TIFF) |
| .tiff | `yolo predict source=image.tiff` | [Tag Image File Format](https://en.wikipedia.org/wiki/TIFF) |
| .webp | `yolo predict source=image.webp` | [WebP](https://en.wikipedia.org/wiki/WebP) |
| .pfm | `yolo predict source=image.pfm` | [Portable FloatMap](https://en.wikipedia.org/wiki/Netpbm#File_formats) |
### Video Suffixes
| Video Suffixes | Example Predict Command | Reference |
|----------------|----------------------------------|----------------------------------------------------------------------------------|
| .asf | `yolo predict source=video.asf` | [Advanced Systems Format](https://en.wikipedia.org/wiki/Advanced_Systems_Format) |
| .avi | `yolo predict source=video.avi` | [Audio Video Interleave](https://en.wikipedia.org/wiki/Audio_Video_Interleave) |
| .gif | `yolo predict source=video.gif` | [Graphics Interchange Format](https://en.wikipedia.org/wiki/GIF) |
| .m4v | `yolo predict source=video.m4v` | [MPEG-4 Part 14](https://en.wikipedia.org/wiki/M4V) |
| .mkv | `yolo predict source=video.mkv` | [Matroska](https://en.wikipedia.org/wiki/Matroska) |
| .mov | `yolo predict source=video.mov` | [QuickTime File Format](https://en.wikipedia.org/wiki/QuickTime_File_Format) |
| .mp4 | `yolo predict source=video.mp4` | [MPEG-4 Part 14 - Wikipedia](https://en.wikipedia.org/wiki/MPEG-4_Part_14) |
| .mpeg | `yolo predict source=video.mpeg` | [MPEG-1 Part 2](https://en.wikipedia.org/wiki/MPEG-1) |
| .mpg | `yolo predict source=video.mpg` | [MPEG-1 Part 2](https://en.wikipedia.org/wiki/MPEG-1) |
| .ts | `yolo predict source=video.ts` | [MPEG Transport Stream](https://en.wikipedia.org/wiki/MPEG_transport_stream) |
| .wmv | `yolo predict source=video.wmv` | [Windows Media Video](https://en.wikipedia.org/wiki/Windows_Media_Video) |
| .webm | `yolo predict source=video.webm` | [WebM Project](https://en.wikipedia.org/wiki/WebM) |
## Working with Results
The `Results` object contains the following components:
- `Results.boxes`: `Boxes` object with properties and methods for manipulating bounding boxes
- `Results.masks`: `Masks` object for indexing masks or getting segment coordinates
- `Results.probs`: `torch.Tensor` containing class probabilities or logits
- `Results.orig_img`: Original image loaded in memory
- `Results.path`: `Path` containing the path to the input image
Each result is composed of a `torch.Tensor` by default, which allows for easy manipulation:
!!! example "Results"
```python
results = results.cuda()
results = results.cpu()
results = results.to('cpu')
results = results.numpy()
```
### Boxes
`Boxes` object can be used to index, manipulate, and convert bounding boxes to different formats. Box format conversion
operations are cached, meaning they're only calculated once per object, and those values are reused for future calls.
- Indexing a `Boxes` object returns a `Boxes` object:
!!! example "Boxes"
```python
results = model(img)
boxes = results[0].boxes
box = boxes[0] # returns one box
box.xyxy
```
- Properties and conversions
!!! example "Boxes Properties"
```python
boxes.xyxy # box with xyxy format, (N, 4)
boxes.xywh # box with xywh format, (N, 4)
boxes.xyxyn # box with xyxy format but normalized, (N, 4)
boxes.xywhn # box with xywh format but normalized, (N, 4)
boxes.conf # confidence score, (N, 1)
boxes.cls # cls, (N, 1)
boxes.data # raw bboxes tensor, (N, 6) or boxes.boxes
```
### Masks
`Masks` object can be used index, manipulate and convert masks to segments. The segment conversion operation is cached.
!!! example "Masks"
```python
results = model(inputs)
masks = results[0].masks # Masks object
masks.segments # bounding coordinates of masks, List[segment] * N
masks.data # raw masks tensor, (N, H, W) or masks.masks
```
### probs
`probs` attribute of `Results` class is a `Tensor` containing class probabilities of a classification operation.
!!! example "Probs"
```python
results = model(inputs)
results[0].probs # cls prob, (num_class, )
```
Class reference documentation for `Results` module and its components can be found [here](../reference/results.md)
## Plotting results
You can use `plot()` function of `Result` object to plot results on in image object. It plots all components(boxes,
masks, classification logits, etc.) found in the results object
!!! example "Plotting"
```python
res = model(img)
res_plotted = res[0].plot()
cv2.imshow("result", res_plotted)
```
- `show_conf (bool)`: Show confidence
- `line_width (Float)`: The line width of boxes. Automatically scaled to img size if not provided
- `font_size (Float)`: The font size of . Automatically scaled to img size if not provided