yair 69dcea025e Add rollingsum filter for frame analysis based on column mean deviation
- Implements GStreamer element that analyzes pixel columns
- Drops frames when column mean deviates from rolling baseline
- Configurable window size, column index, stride, and threshold
- Includes design documentation and build script
- Tested successfully with IDS uEye camera source
2025-11-14 03:44:54 +02:00

144 lines
5.0 KiB
Python

import numpy as np
import imageio.v3 as iio
from tqdm import tqdm
import concurrent.futures
import os
# --- Configuration ---
DATA_SOURCE = "data/760-004_cropped_ZTjMVf.avi"
RING_BUFFER_SIZE = 32000
OUTPUT_DIR = "output"
os.makedirs(OUTPUT_DIR, exist_ok=True)
write_executor = concurrent.futures.ThreadPoolExecutor(max_workers=2)
futures = []
def submit_write_job(ring_buffer, index, length, ring_index):
try:
# copy data so it doesnt run away
data_to_write = np.take(ring_buffer, range(ring_index-length, ring_index), axis=0, mode='wrap').copy()
except Exception as e:
print(f"Error taking data from ring buffer: {e}")
return None
def _write_task(data):
filename = f"{OUTPUT_DIR}/object-{index-length}-{index}-{length}.png"
iio.imwrite(filename, data)
future = write_executor.submit(_write_task, data_to_write)
return future
props = iio.improps(DATA_SOURCE) # overwrite manually if live video source
window_size = 12000
ema_mean = 0.74
ema_var = 0.05
baseline_alpha = 0.001
variance_alpha = 0.01
default_diff = 0.52
stride=1
frameskip=1
postcutoff_variance_threshold = 2.5
cutoff_variance_threshold = 3.5
precutoff_variance_threshold = 0.05
is_recording = False
recording_length = 0
patience_default = 600
patience = patience_default
patience_length = 0
recorded_images = 0
frames_since_last_recording = 0
index = 0
ring_buffer = np.zeros((RING_BUFFER_SIZE, props.shape[2], props.shape[3]), dtype=props.dtype)
sum_ring_buffer = np.zeros((RING_BUFFER_SIZE), dtype=np.uint64)
ema_var_ring = np.zeros((RING_BUFFER_SIZE), dtype=np.float32)
sum_buffer = np.zeros_like(sum_ring_buffer[0:window_size])
stride_indices = np.arange(0, props.shape[2], stride)
for frame in tqdm(iio.imiter(DATA_SOURCE, plugin="pyav"), total=props.n_images):
effective_window_size = min(index, window_size)
ring_index = index%RING_BUFFER_SIZE
time_indices = np.arange(ring_index - effective_window_size, ring_index) % RING_BUFFER_SIZE
sum_buffer[:len(time_indices)] = sum_ring_buffer[time_indices[:]]
# splayed out for perf debugging
s4 = frame[0:1,::stride,1]
frame_mean = np.divide(np.sum(s4),s4.size)
s2 = sum_buffer[:len(time_indices)]
s11 = np.sum(s2)
s1 = np.divide(s11,s2.size) if s2.size > 0 else 0 # Avoid division by zero
s0 = np.abs(frame_mean - s1)
s00 = np.mean(s0)
value = s00 if index > 0 else default_diff
if ema_mean is None:
ema_mean, ema_var = value, 1.0
deviation = value - ema_mean
ema_mean_temp = (1 - baseline_alpha) * ema_mean + baseline_alpha * value
ema_var_temp = (1 - variance_alpha) * ema_var + variance_alpha * (deviation ** 2)
ring_buffer[ring_index:ring_index+1, :, :] = frame[0:1,:,:]
sum_ring_buffer[ring_index] = frame_mean
if is_recording == False or abs(deviation) < 3 * np.sqrt(ema_var):
ema_var = ema_var_temp
ema_mean = ema_mean_temp
if (is_recording == False and ema_var > cutoff_variance_threshold):
is_recording = True
quiet_indices = np.argwhere(np.take(ema_var_ring, range(ring_index-RING_BUFFER_SIZE, ring_index), mode='wrap') < precutoff_variance_threshold)
if quiet_indices.size > 0:
last_quiet_index = quiet_indices[-1].item()
recording_length = min(RING_BUFFER_SIZE - last_quiet_index + patience_default, frames_since_last_recording)
else:
recording_length = frames_since_last_recording
patience = patience_default
patience_length = 0
if is_recording:
if (ema_var < postcutoff_variance_threshold):
patience -= 1
patience_length += 1
if (ema_var >= postcutoff_variance_threshold):
recording_length += 1
patience_length = 0
patience = patience_default
if (patience == 0):
print(f"Dumping image starting at index {index-recording_length} ending at {index}, length {recording_length}")
future = submit_write_job(ring_buffer, index, recording_length, ring_index-patience_length)
if future:
futures.append(future)
ema_var_ring[ring_index-patience_length] = 0.0
recorded_images += 1
frames_since_last_recording = patience_length
patience_length = 0
is_recording = False
ema_var_ring[ring_index] = ema_var
index += 1
frames_since_last_recording += 1
# handle final recording
if is_recording:
print(f"Dumping final image starting at index {index-recording_length} ending at {index}, length {recording_length}")
final_future = submit_write_job(ring_buffer, index, recording_length, ring_index-patience_length)
if final_future:
futures.append(final_future)
recorded_images += 1
# wait for image writes to complete
print("Processing complete. Waiting for all background writing tasks to finish...")
concurrent.futures.wait(futures)
write_executor.shutdown() # Cleanly release resources
print(f"All images written. Recorded {recorded_images} objects.")