File size: 3,531 Bytes
a44124f | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 | #!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Video frame subsampling script
Subsample frames by taking every N-th frame to reduce total frame count.
"""
import os
import shutil
from pathlib import Path
from tqdm import tqdm
def subsample_video_dataset(
src_dir: str,
dst_dir: str,
step: int = 2,
frame_pattern: str = "*_t*.png"
):
"""
Subsample video dataset frames
Args:
src_dir: Source directory (e.g., Dataset/vedio)
dst_dir: Destination directory (e.g., Dataset/vedio_half)
step: Sampling step (2 means take every 2nd frame)
frame_pattern: Frame file pattern
"""
src_path = Path(src_dir)
dst_path = Path(dst_dir)
# Create destination directory
dst_path.mkdir(parents=True, exist_ok=True)
# Statistics
total_videos = 0
total_src_frames = 0
total_dst_frames = 0
# Iterate class directories (lumen, lumen_collapse, non_lumen)
for class_dir in sorted(src_path.iterdir()):
if not class_dir.is_dir():
continue
class_name = class_dir.name
dst_class_dir = dst_path / class_name
dst_class_dir.mkdir(exist_ok=True)
print(f"\nProcessing class: {class_name}")
# Iterate video directories
video_dirs = sorted([d for d in class_dir.iterdir() if d.is_dir()])
for video_dir in tqdm(video_dirs, desc=f" {class_name}"):
video_name = video_dir.name
dst_video_dir = dst_class_dir / video_name
dst_video_dir.mkdir(exist_ok=True)
# Get all frame files and sort
frame_files = sorted(video_dir.glob(frame_pattern))
if len(frame_files) == 0:
continue
total_videos += 1
total_src_frames += len(frame_files)
# Take every N-th frame
sampled_frames = frame_files[::step]
total_dst_frames += len(sampled_frames)
# Copy and rename
# Extract prefix from original filename (e.g., "lumen_1" from "lumen_1_t000.png")
first_frame_name = frame_files[0].name
prefix = first_frame_name.rsplit('_t', 1)[0]
for new_idx, src_frame in enumerate(sampled_frames):
# New filename: prefix_t{new_idx:03d}.png
new_name = f"{prefix}_t{new_idx:03d}.png"
dst_frame = dst_video_dir / new_name
shutil.copy2(src_frame, dst_frame)
print(f"\n{'='*50}")
print(f"Subsampling complete!")
print(f" Source dir: {src_dir}")
print(f" Dest dir: {dst_dir}")
print(f" Step: every {step} frames")
print(f" Total videos: {total_videos}")
print(f" Original frames: {total_src_frames}")
print(f" Subsampled frames: {total_dst_frames}")
print(f" Compression ratio: {total_src_frames / total_dst_frames:.2f}x")
print(f"{'='*50}")
if __name__ == "__main__":
import argparse
parser = argparse.ArgumentParser(description='Subsample video frames')
parser.add_argument('--src', type=str, default='Dataset/vedio',
help='Source video directory')
parser.add_argument('--dst', type=str, default='Dataset/vedio_half',
help='Destination directory')
parser.add_argument('--step', type=int, default=2,
help='Sampling step (2=take every 2nd frame)')
args = parser.parse_args()
subsample_video_dataset(
src_dir=args.src,
dst_dir=args.dst,
step=args.step,
)
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