scrcpy/doc/video.md

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# Video
## Size
By default, scrcpy attempts to mirror at the Android device resolution.
It might be useful to mirror at a lower definition to increase performance. To
limit both width and height to some maximum value (here 1024):
```bash
scrcpy --max-size=1024
scrcpy -m 1024 # short version
```
The other dimension is computed so that the Android device aspect ratio is
preserved. That way, a device in 1920×1080 will be mirrored at 1024×576.
If encoding fails, scrcpy automatically tries again with a lower definition
(unless `--no-downsize-on-error` is enabled).
## Bit rate
2023-03-20 07:35:13 +00:00
The default video bit rate is 8 Mbps. To change it:
```bash
scrcpy --video-bit-rate=2M
scrcpy --video-bit-rate=2000000 # equivalent
scrcpy -b 2M # short version
```
## Frame rate
The capture frame rate can be limited:
```bash
scrcpy --max-fps=15
```
The actual capture frame rate may be printed to the console:
```
scrcpy --print-fps
```
It may also be enabled or disabled at anytime with <kbd>MOD</kbd>+<kbd>i</kbd>
(see [shortcuts](shortcuts.md)).
The frame rate is intrinsically variable: a new frame is produced only when the
screen content changes. For example, if you play a fullscreen video at 24fps on
your device, you should not get more than 24 frames per second in scrcpy.
## Codec
The video codec can be selected. The possible values are `h264` (default),
`h265` and `av1`:
```bash
scrcpy --video-codec=h264 # default
scrcpy --video-codec=h265
scrcpy --video-codec=av1
```
H265 may provide better quality, but H264 should provide lower latency.
AV1 encoders are not common on current Android devices.
For advanced usage, to pass arbitrary parameters to the [`MediaFormat`],
check `--video-codec-options` in the manpage or in `scrcpy --help`.
[`MediaFormat`]: https://developer.android.com/reference/android/media/MediaFormat
## Encoder
Several encoders may be available on the device. They can be listed by:
```bash
scrcpy --list-encoders
```
Sometimes, the default encoder may have issues or even crash, so it is useful to
try another one:
```bash
scrcpy --video-codec=h264 --video-encoder='OMX.qcom.video.encoder.avc'
```
## Rotation
The rotation may be applied at 3 different levels:
- The [shortcut](shortcuts.md) <kbd>MOD</kbd>+<kbd>r</kbd> requests the
device to switch between portrait and landscape (the current running app may
refuse, if it does not support the requested orientation).
- `--lock-video-orientation` changes the mirroring orientation (the orientation
of the video sent from the device to the computer). This affects the
recording.
- `--rotation` rotates only the window content. This only affects the display,
not the recording. It may be changed dynamically at any time using the
[shortcuts](shortcuts.md) <kbd>MOD</kbd>+<kbd></kbd> and
<kbd>MOD</kbd>+<kbd></kbd>.
To lock the mirroring orientation:
```bash
scrcpy --lock-video-orientation # initial (current) orientation
scrcpy --lock-video-orientation=0 # natural orientation
scrcpy --lock-video-orientation=1 # 90° counterclockwise
scrcpy --lock-video-orientation=2 # 180°
scrcpy --lock-video-orientation=3 # 90° clockwise
```
To set an initial window rotation:
```bash
scrcpy --rotation=0 # no rotation
scrcpy --rotation=1 # 90 degrees counterclockwise
scrcpy --rotation=2 # 180 degrees
scrcpy --rotation=3 # 90 degrees clockwise
```
## Crop
The device screen may be cropped to mirror only part of the screen.
This is useful, for example, to mirror only one eye of the Oculus Go:
```bash
scrcpy --crop=1224:1440:0:0 # 1224x1440 at offset (0,0)
```
The values are expressed in the device natural orientation (portrait for a
phone, landscape for a tablet).
If `--max-size` is also specified, resizing is applied after cropping.
## Display
If several displays are available on the Android device, it is possible to
select the display to mirror:
```bash
scrcpy --display=1
```
The list of display ids can be retrieved by:
```bash
scrcpy --list-displays
```
A secondary display may only be controlled if the device runs at least Android
10 (otherwise it is mirrored as read-only).
## Buffering
By default, there is no video buffering, to get the lowest possible latency.
Buffering can be added to delay the video stream and compensate for jitter to
get a smoother playback (see [#2464]).
[#2464]: https://github.com/Genymobile/scrcpy/issues/2464
The configuration is available independently for the display,
[v4l2 sinks](video.md#video4linux) and [audio](audio.md#buffering) playback.
```bash
scrcpy --display-buffer=50 # add 50ms buffering for display
scrcpy --v4l2-buffer=300 # add 300ms buffering for v4l2 sink
scrcpy --audio-buffer=200 # set 200ms buffering for audio playback
```
They can be applied simultaneously:
```bash
scrcpy --display-buffer=50 --v4l2-buffer=300
```
## No playback
It is possible to capture an Android device without playing video or audio on
the computer. This option is useful when [recording](recording.md) or when
[v4l2](#video4linux) is enabled:
```bash
scrcpy --v4l2-sink=/dev/video2 --no-playback
scrcpy --record=file.mkv --no-playback
# interrupt with Ctrl+C
```
It is also possible to disable video and audio playback separately:
```bash
# Send video to V4L2 sink without playing it, but keep audio playback
scrcpy --v4l2-sink=/dev/video2 --no-video-playback
# Record both video and audio, but only play video
scrcpy --record=file.mkv --no-audio-playback
```
## No video
To disable video forwarding completely, so that only audio is forwarded:
```
scrcpy --no-video
```
## Video4Linux
See the dedicated [Video4Linux](v4l2.md) page.