framerate during video

[BUDMAN65]

Can anyone give an example of setting the framerate during video recording?

[davidplowman]

After calling picam2.configure(config) and before picam2.start() use picam2.set_controls({"FrameDurationLimits": (33333, 33333)}).

The two numbers are the maximum and minimum frame times in usecs. So this example would give you fixed 30fps.

[andrewsg3]

Following the guidance in 4.2.2.3 of the picamera2 manual I have attempted to manually configure sensor mode

import picamera2
import time

picam2 = picamera2.Picamera2()

mode = picam2.sensor_modes[0]

print(f"Selected mode has size {mode['size']}, bit depth {mode['bit_depth']} and fps {mode['fps']}.")

config = picam2.create_video_configuration(sensor={'output_size': mode['size'], 'bit_depth':
mode['bit_depth']})

picam2.configure(config)

target_fps = 120

frame_limits = int(1000000/target_fps)

print(f"Target fps = {target_fps}, frame duration limits = {frame_limits}, {frame_limits}")

config = picam2.create_video_configuration(
        main={"size": (1332,990)},
        controls={"FrameDurationLimits": [frame_limits, frame_limits]}
)

picam2.configure(config)

encoder = picamera2.encoders.H264Encoder(bitrate=1000000)

filename = f"picamera2_{target_fps}fps.mp4"
output = picamera2.outputs.FileOutput(filename)

picam2.start_recording(encoder, output)

time.sleep(5)

picam2.stop_recording()

Again ffprobe reports 30fps, video is slow, and the sensor configuration does not match rpicam-vid

Edit: more code tags fixed

[davidplowman]

Hi, so it looks like you've more or less figured everything out, you've got it to choose the right camera mode (often a stumbling block!) and so on.

But the obvious problem is that you're using the FileOutput. This writes an unencapsulated raw H.264 bistream to a file. It so happens you're calling it ".mp4" but that doesn't make it an mp4 file! Raw H.264 bitstreams don't contain timestamps, and any software reading it (if it can read it) may just default to 30fps.

You need to choose an output that can write a real mp4 file, like this:

import time
from picamera2 import Picamera2
from picamera2.encoders import H264Encoder
from picamera2.outputs import PyavOutput

picam2 = Picamera2()

mode = picam2.sensor_modes[0]

sensor = {'output_size': mode['size'], 'bit_depth': mode['bit_depth']}

main = {'size': (1332, 990)}
controls = {'FrameRate': 120}
config = picam2.create_video_configuration(main, sensor=sensor, controls=controls)
picam2.configure(config)

encoder = H264Encoder(bitrate=10000000)
output = PyavOutput("test.mp4")

picam2.start_recording(encoder, output)

time.sleep(5)

picam2.stop_recording()

I'm getting about 118fps here according to ffprobe. Note that 1332x990@120fps is probably slightly exceeding the system's capabilities. We quote 1080p30 as being supported, but note that a Pi 5 should normally get up to about 1080p50. In terms of pixel throughput, that's about the same as 720p100 so the limit will be somewhere around there. For me, 720p120 seems to work OK, but it doesn't quite keep up at 1332x990@120, but it's very close.

[andrewsg3]

Thank you so much, been able to achieve approximately 99fps with that code which is great.

[davidplowman]

A couple of other thoughts. If you set the main stream format to "YUV420" that may give you better performance. Also maybe try increasing buffer_count in create_video_configuration. Maybe try buffer_count=16.

[andrewsg3]

Yes! That bumped it to 119.44fps. You don't know how much stress this has saved me! Thanks again :)