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							559 lines
						
					
					
						
							15 KiB
						
					
					
				| import json
 | |
| import os
 | |
| import pickle
 | |
| import struct
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| import subprocess
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| import threading
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| from enum import IntEnum
 | |
| from functools import wraps
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| 
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| import numpy as np
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| from lru import LRU
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| 
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| import _io
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| from openpilot.tools.lib.cache import cache_path_for_file_path, DEFAULT_CACHE_DIR
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| from openpilot.tools.lib.exceptions import DataUnreadableError
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| from openpilot.tools.lib.vidindex import hevc_index
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| from openpilot.common.file_helpers import atomic_write_in_dir
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| 
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| from openpilot.tools.lib.filereader import FileReader, resolve_name
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| 
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| HEVC_SLICE_B = 0
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| HEVC_SLICE_P = 1
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| HEVC_SLICE_I = 2
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| 
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| 
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| class GOPReader:
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|   def get_gop(self, num):
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|     # returns (start_frame_num, num_frames, frames_to_skip, gop_data)
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|     raise NotImplementedError
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| 
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| 
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| class DoNothingContextManager:
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|   def __enter__(self):
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|     return self
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| 
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|   def __exit__(self, *x):
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|     pass
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| 
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| 
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| class FrameType(IntEnum):
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|   raw = 1
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|   h265_stream = 2
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| 
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| 
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| def fingerprint_video(fn):
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|   with FileReader(fn) as f:
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|     header = f.read(4)
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|   if len(header) == 0:
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|     raise DataUnreadableError(f"{fn} is empty")
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|   elif header == b"\x00\xc0\x12\x00":
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|     return FrameType.raw
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|   elif header == b"\x00\x00\x00\x01":
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|     if 'hevc' in fn:
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|       return FrameType.h265_stream
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|     else:
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|       raise NotImplementedError(fn)
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|   else:
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|     raise NotImplementedError(fn)
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| 
 | |
| 
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| def ffprobe(fn, fmt=None):
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|   fn = resolve_name(fn)
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|   cmd = ["ffprobe", "-v", "quiet", "-print_format", "json", "-show_format", "-show_streams"]
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|   if fmt:
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|     cmd += ["-f", fmt]
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|   cmd += ["-i", "-"]
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| 
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|   try:
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|     with FileReader(fn) as f:
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|       ffprobe_output = subprocess.check_output(cmd, input=f.read(4096))
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|   except subprocess.CalledProcessError as e:
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|     raise DataUnreadableError(fn) from e
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| 
 | |
|   return json.loads(ffprobe_output)
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| 
 | |
| 
 | |
| def cache_fn(func):
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|   @wraps(func)
 | |
|   def cache_inner(fn, *args, **kwargs):
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|     if kwargs.pop('no_cache', None):
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|       cache_path = None
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|     else:
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|       cache_dir = kwargs.pop('cache_dir', DEFAULT_CACHE_DIR)
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|       cache_path = cache_path_for_file_path(fn, cache_dir)
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| 
 | |
|     if cache_path and os.path.exists(cache_path):
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|       with open(cache_path, "rb") as cache_file:
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|         cache_value = pickle.load(cache_file)
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|     else:
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|       cache_value = func(fn, *args, **kwargs)
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|       if cache_path:
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|         with atomic_write_in_dir(cache_path, mode="wb", overwrite=True) as cache_file:
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|           pickle.dump(cache_value, cache_file, -1)
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| 
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|     return cache_value
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| 
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|   return cache_inner
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| 
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| 
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| @cache_fn
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| def index_stream(fn, ft):
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|   if ft != FrameType.h265_stream:
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|     raise NotImplementedError("Only h265 supported")
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| 
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|   frame_types, dat_len, prefix = hevc_index(fn)
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|   index = np.array(frame_types + [(0xFFFFFFFF, dat_len)], dtype=np.uint32)
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|   probe = ffprobe(fn, "hevc")
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| 
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|   return {
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|     'index': index,
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|     'global_prefix': prefix,
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|     'probe': probe
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|   }
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| 
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| 
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| def get_video_index(fn, frame_type, cache_dir=DEFAULT_CACHE_DIR):
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|   return index_stream(fn, frame_type, cache_dir=cache_dir)
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| 
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| def read_file_check_size(f, sz, cookie):
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|   buff = bytearray(sz)
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|   bytes_read = f.readinto(buff)
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|   assert bytes_read == sz, (bytes_read, sz)
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|   return buff
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| 
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| 
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| def rgb24toyuv(rgb):
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|   yuv_from_rgb = np.array([[ 0.299     ,  0.587     ,  0.114      ],
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|                            [-0.14714119, -0.28886916,  0.43601035 ],
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|                            [ 0.61497538, -0.51496512, -0.10001026 ]])
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|   img = np.dot(rgb.reshape(-1, 3), yuv_from_rgb.T).reshape(rgb.shape)
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| 
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| 
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| 
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|   ys = img[:, :, 0]
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|   us = (img[::2, ::2, 1] + img[1::2, ::2, 1] + img[::2, 1::2, 1] + img[1::2, 1::2, 1]) / 4 + 128
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|   vs = (img[::2, ::2, 2] + img[1::2, ::2, 2] + img[::2, 1::2, 2] + img[1::2, 1::2, 2]) / 4 + 128
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| 
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|   return ys, us, vs
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| 
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| 
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| def rgb24toyuv420(rgb):
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|   ys, us, vs = rgb24toyuv(rgb)
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| 
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|   y_len = rgb.shape[0] * rgb.shape[1]
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|   uv_len = y_len // 4
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| 
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|   yuv420 = np.empty(y_len + 2 * uv_len, dtype=rgb.dtype)
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|   yuv420[:y_len] = ys.reshape(-1)
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|   yuv420[y_len:y_len + uv_len] = us.reshape(-1)
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|   yuv420[y_len + uv_len:y_len + 2 * uv_len] = vs.reshape(-1)
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| 
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|   return yuv420.clip(0, 255).astype('uint8')
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| 
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| 
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| def rgb24tonv12(rgb):
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|   ys, us, vs = rgb24toyuv(rgb)
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| 
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|   y_len = rgb.shape[0] * rgb.shape[1]
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|   uv_len = y_len // 4
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| 
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|   nv12 = np.empty(y_len + 2 * uv_len, dtype=rgb.dtype)
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|   nv12[:y_len] = ys.reshape(-1)
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|   nv12[y_len::2] = us.reshape(-1)
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|   nv12[y_len+1::2] = vs.reshape(-1)
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| 
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|   return nv12.clip(0, 255).astype('uint8')
 | |
| 
 | |
| 
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| def decompress_video_data(rawdat, vid_fmt, w, h, pix_fmt):
 | |
|   threads = os.getenv("FFMPEG_THREADS", "0")
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|   cuda = os.getenv("FFMPEG_CUDA", "0") == "1"
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|   args = ["ffmpeg", "-v", "quiet",
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|           "-threads", threads,
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|           "-hwaccel", "none" if not cuda else "cuda",
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|           "-c:v", "hevc",
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|           "-vsync", "0",
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|           "-f", vid_fmt,
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|           "-flags2", "showall",
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|           "-i", "-",
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|           "-threads", threads,
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|           "-f", "rawvideo",
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|           "-pix_fmt", pix_fmt,
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|           "-"]
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|   dat = subprocess.check_output(args, input=rawdat)
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| 
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|   if pix_fmt == "rgb24":
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|     ret = np.frombuffer(dat, dtype=np.uint8).reshape(-1, h, w, 3)
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|   elif pix_fmt == "nv12":
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|     ret = np.frombuffer(dat, dtype=np.uint8).reshape(-1, (h*w*3//2))
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|   elif pix_fmt == "yuv420p":
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|     ret = np.frombuffer(dat, dtype=np.uint8).reshape(-1, (h*w*3//2))
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|   elif pix_fmt == "yuv444p":
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|     ret = np.frombuffer(dat, dtype=np.uint8).reshape(-1, 3, h, w)
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|   else:
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|     raise NotImplementedError
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| 
 | |
|   return ret
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| 
 | |
| 
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| class BaseFrameReader:
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|   # properties: frame_type, frame_count, w, h
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| 
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|   def __enter__(self):
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|     return self
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| 
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|   def __exit__(self, *args):
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|     self.close()
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| 
 | |
|   def close(self):
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|     pass
 | |
| 
 | |
|   def get(self, num, count=1, pix_fmt="yuv420p"):
 | |
|     raise NotImplementedError
 | |
| 
 | |
| 
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| def FrameReader(fn, cache_dir=DEFAULT_CACHE_DIR, readahead=False, readbehind=False, index_data=None):
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|   frame_type = fingerprint_video(fn)
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|   if frame_type == FrameType.raw:
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|     return RawFrameReader(fn)
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|   elif frame_type in (FrameType.h265_stream,):
 | |
|     if not index_data:
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|       index_data = get_video_index(fn, frame_type, cache_dir)
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|     return StreamFrameReader(fn, frame_type, index_data, readahead=readahead, readbehind=readbehind)
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|   else:
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|     raise NotImplementedError(frame_type)
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| 
 | |
| 
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| class RawData:
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|   def __init__(self, f):
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|     self.f = _io.FileIO(f, 'rb')
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|     self.lenn = struct.unpack("I", self.f.read(4))[0]
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|     self.count = os.path.getsize(f) / (self.lenn+4)
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| 
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|   def read(self, i):
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|     self.f.seek((self.lenn+4)*i + 4)
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|     return self.f.read(self.lenn)
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| 
 | |
| 
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| class RawFrameReader(BaseFrameReader):
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|   def __init__(self, fn):
 | |
|     # raw camera
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|     self.fn = fn
 | |
|     self.frame_type = FrameType.raw
 | |
|     self.rawfile = RawData(self.fn)
 | |
|     self.frame_count = self.rawfile.count
 | |
|     self.w, self.h = 640, 480
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| 
 | |
|   def load_and_debayer(self, img):
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|     img = np.frombuffer(img, dtype='uint8').reshape(960, 1280)
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|     cimg = np.dstack([img[0::2, 1::2], ((img[0::2, 0::2].astype("uint16") + img[1::2, 1::2].astype("uint16")) >> 1).astype("uint8"), img[1::2, 0::2]])
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|     return cimg
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| 
 | |
|   def get(self, num, count=1, pix_fmt="yuv420p"):
 | |
|     assert self.frame_count is not None
 | |
|     assert num+count <= self.frame_count
 | |
| 
 | |
|     if pix_fmt not in ("nv12", "yuv420p", "rgb24"):
 | |
|       raise ValueError(f"Unsupported pixel format {pix_fmt!r}")
 | |
| 
 | |
|     app = []
 | |
|     for i in range(num, num+count):
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|       dat = self.rawfile.read(i)
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|       rgb_dat = self.load_and_debayer(dat)
 | |
|       if pix_fmt == "rgb24":
 | |
|         app.append(rgb_dat)
 | |
|       elif pix_fmt == "nv12":
 | |
|         app.append(rgb24tonv12(rgb_dat))
 | |
|       elif pix_fmt == "yuv420p":
 | |
|         app.append(rgb24toyuv420(rgb_dat))
 | |
|       else:
 | |
|         raise NotImplementedError
 | |
| 
 | |
|     return app
 | |
| 
 | |
| 
 | |
| class VideoStreamDecompressor:
 | |
|   def __init__(self, fn, vid_fmt, w, h, pix_fmt):
 | |
|     self.fn = fn
 | |
|     self.vid_fmt = vid_fmt
 | |
|     self.w = w
 | |
|     self.h = h
 | |
|     self.pix_fmt = pix_fmt
 | |
| 
 | |
|     if pix_fmt in ("nv12", "yuv420p"):
 | |
|       self.out_size = w*h*3//2  # yuv420p
 | |
|     elif pix_fmt in ("rgb24", "yuv444p"):
 | |
|       self.out_size = w*h*3
 | |
|     else:
 | |
|       raise NotImplementedError
 | |
| 
 | |
|     self.proc = None
 | |
|     self.t = threading.Thread(target=self.write_thread)
 | |
|     self.t.daemon = True
 | |
| 
 | |
|   def write_thread(self):
 | |
|     try:
 | |
|       with FileReader(self.fn) as f:
 | |
|         while True:
 | |
|           r = f.read(1024*1024)
 | |
|           if len(r) == 0:
 | |
|             break
 | |
|           self.proc.stdin.write(r)
 | |
|     except BrokenPipeError:
 | |
|       pass
 | |
|     finally:
 | |
|       self.proc.stdin.close()
 | |
| 
 | |
|   def read(self):
 | |
|     threads = os.getenv("FFMPEG_THREADS", "0")
 | |
|     cuda = os.getenv("FFMPEG_CUDA", "0") == "1"
 | |
|     cmd = [
 | |
|       "ffmpeg",
 | |
|       "-threads", threads,
 | |
|       "-hwaccel", "none" if not cuda else "cuda",
 | |
|       "-c:v", "hevc",
 | |
|       # "-avioflags", "direct",
 | |
|       "-analyzeduration", "0",
 | |
|       "-probesize", "32",
 | |
|       "-flush_packets", "0",
 | |
|       # "-fflags", "nobuffer",
 | |
|       "-vsync", "0",
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|       "-f", self.vid_fmt,
 | |
|       "-i", "pipe:0",
 | |
|       "-threads", threads,
 | |
|       "-f", "rawvideo",
 | |
|       "-pix_fmt", self.pix_fmt,
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|       "pipe:1"
 | |
|     ]
 | |
|     self.proc = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
 | |
|     try:
 | |
|       self.t.start()
 | |
| 
 | |
|       while True:
 | |
|         dat = self.proc.stdout.read(self.out_size)
 | |
|         if len(dat) == 0:
 | |
|           break
 | |
|         assert len(dat) == self.out_size
 | |
|         if self.pix_fmt == "rgb24":
 | |
|           ret = np.frombuffer(dat, dtype=np.uint8).reshape((self.h, self.w, 3))
 | |
|         elif self.pix_fmt == "yuv420p":
 | |
|           ret = np.frombuffer(dat, dtype=np.uint8)
 | |
|         elif self.pix_fmt == "nv12":
 | |
|           ret = np.frombuffer(dat, dtype=np.uint8)
 | |
|         elif self.pix_fmt == "yuv444p":
 | |
|           ret = np.frombuffer(dat, dtype=np.uint8).reshape((3, self.h, self.w))
 | |
|         else:
 | |
|           raise RuntimeError(f"unknown pix_fmt: {self.pix_fmt}")
 | |
|         yield ret
 | |
| 
 | |
|       result_code = self.proc.wait()
 | |
|       assert result_code == 0, result_code
 | |
|     finally:
 | |
|       self.proc.kill()
 | |
|       self.t.join()
 | |
| 
 | |
| class StreamGOPReader(GOPReader):
 | |
|   def __init__(self, fn, frame_type, index_data):
 | |
|     assert frame_type == FrameType.h265_stream
 | |
| 
 | |
|     self.fn = fn
 | |
| 
 | |
|     self.frame_type = frame_type
 | |
|     self.frame_count = None
 | |
|     self.w, self.h = None, None
 | |
| 
 | |
|     self.prefix = None
 | |
|     self.index = None
 | |
| 
 | |
|     self.index = index_data['index']
 | |
|     self.prefix = index_data['global_prefix']
 | |
|     probe = index_data['probe']
 | |
| 
 | |
|     self.prefix_frame_data = None
 | |
|     self.num_prefix_frames = 0
 | |
|     self.vid_fmt = "hevc"
 | |
| 
 | |
|     i = 0
 | |
|     while i < self.index.shape[0] and self.index[i, 0] != HEVC_SLICE_I:
 | |
|       i += 1
 | |
|     self.first_iframe = i
 | |
| 
 | |
|     assert self.first_iframe == 0
 | |
| 
 | |
|     self.frame_count = len(self.index) - 1
 | |
| 
 | |
|     self.w = probe['streams'][0]['width']
 | |
|     self.h = probe['streams'][0]['height']
 | |
| 
 | |
|   def _lookup_gop(self, num):
 | |
|     frame_b = num
 | |
|     while frame_b > 0 and self.index[frame_b, 0] != HEVC_SLICE_I:
 | |
|       frame_b -= 1
 | |
| 
 | |
|     frame_e = num + 1
 | |
|     while frame_e < (len(self.index) - 1) and self.index[frame_e, 0] != HEVC_SLICE_I:
 | |
|       frame_e += 1
 | |
| 
 | |
|     offset_b = self.index[frame_b, 1]
 | |
|     offset_e = self.index[frame_e, 1]
 | |
| 
 | |
|     return (frame_b, frame_e, offset_b, offset_e)
 | |
| 
 | |
|   def get_gop(self, num):
 | |
|     frame_b, frame_e, offset_b, offset_e = self._lookup_gop(num)
 | |
|     assert frame_b <= num < frame_e
 | |
| 
 | |
|     num_frames = frame_e - frame_b
 | |
| 
 | |
|     with FileReader(self.fn) as f:
 | |
|       f.seek(offset_b)
 | |
|       rawdat = f.read(offset_e - offset_b)
 | |
| 
 | |
|       if num < self.first_iframe:
 | |
|         assert self.prefix_frame_data
 | |
|         rawdat = self.prefix_frame_data + rawdat
 | |
| 
 | |
|       rawdat = self.prefix + rawdat
 | |
| 
 | |
|     skip_frames = 0
 | |
|     if num < self.first_iframe:
 | |
|       skip_frames = self.num_prefix_frames
 | |
| 
 | |
|     return frame_b, num_frames, skip_frames, rawdat
 | |
| 
 | |
| 
 | |
| class GOPFrameReader(BaseFrameReader):
 | |
|   #FrameReader with caching and readahead for formats that are group-of-picture based
 | |
| 
 | |
|   def __init__(self, readahead=False, readbehind=False):
 | |
|     self.open_ = True
 | |
| 
 | |
|     self.readahead = readahead
 | |
|     self.readbehind = readbehind
 | |
|     self.frame_cache = LRU(64)
 | |
| 
 | |
|     if self.readahead:
 | |
|       self.cache_lock = threading.RLock()
 | |
|       self.readahead_last = None
 | |
|       self.readahead_len = 30
 | |
|       self.readahead_c = threading.Condition()
 | |
|       self.readahead_thread = threading.Thread(target=self._readahead_thread)
 | |
|       self.readahead_thread.daemon = True
 | |
|       self.readahead_thread.start()
 | |
|     else:
 | |
|       self.cache_lock = DoNothingContextManager()
 | |
| 
 | |
|   def close(self):
 | |
|     if not self.open_:
 | |
|       return
 | |
|     self.open_ = False
 | |
| 
 | |
|     if self.readahead:
 | |
|       self.readahead_c.acquire()
 | |
|       self.readahead_c.notify()
 | |
|       self.readahead_c.release()
 | |
|       self.readahead_thread.join()
 | |
| 
 | |
|   def _readahead_thread(self):
 | |
|     while True:
 | |
|       self.readahead_c.acquire()
 | |
|       try:
 | |
|         if not self.open_:
 | |
|           break
 | |
|         self.readahead_c.wait()
 | |
|       finally:
 | |
|         self.readahead_c.release()
 | |
|       if not self.open_:
 | |
|         break
 | |
|       assert self.readahead_last
 | |
|       num, pix_fmt = self.readahead_last
 | |
| 
 | |
|       if self.readbehind:
 | |
|         for k in range(num - 1, max(0, num - self.readahead_len), -1):
 | |
|           self._get_one(k, pix_fmt)
 | |
|       else:
 | |
|         for k in range(num, min(self.frame_count, num + self.readahead_len)):
 | |
|           self._get_one(k, pix_fmt)
 | |
| 
 | |
|   def _get_one(self, num, pix_fmt):
 | |
|     assert num < self.frame_count
 | |
| 
 | |
|     if (num, pix_fmt) in self.frame_cache:
 | |
|       return self.frame_cache[(num, pix_fmt)]
 | |
| 
 | |
|     with self.cache_lock:
 | |
|       if (num, pix_fmt) in self.frame_cache:
 | |
|         return self.frame_cache[(num, pix_fmt)]
 | |
| 
 | |
|       frame_b, num_frames, skip_frames, rawdat = self.get_gop(num)
 | |
| 
 | |
|       ret = decompress_video_data(rawdat, self.vid_fmt, self.w, self.h, pix_fmt)
 | |
|       ret = ret[skip_frames:]
 | |
|       assert ret.shape[0] == num_frames
 | |
| 
 | |
|       for i in range(ret.shape[0]):
 | |
|         self.frame_cache[(frame_b+i, pix_fmt)] = ret[i]
 | |
| 
 | |
|       return self.frame_cache[(num, pix_fmt)]
 | |
| 
 | |
|   def get(self, num, count=1, pix_fmt="yuv420p"):
 | |
|     assert self.frame_count is not None
 | |
| 
 | |
|     if num + count > self.frame_count:
 | |
|       raise ValueError(f"{num + count} > {self.frame_count}")
 | |
| 
 | |
|     if pix_fmt not in ("nv12", "yuv420p", "rgb24", "yuv444p"):
 | |
|       raise ValueError(f"Unsupported pixel format {pix_fmt!r}")
 | |
| 
 | |
|     ret = [self._get_one(num + i, pix_fmt) for i in range(count)]
 | |
| 
 | |
|     if self.readahead:
 | |
|       self.readahead_last = (num+count, pix_fmt)
 | |
|       self.readahead_c.acquire()
 | |
|       self.readahead_c.notify()
 | |
|       self.readahead_c.release()
 | |
| 
 | |
|     return ret
 | |
| 
 | |
| 
 | |
| class StreamFrameReader(StreamGOPReader, GOPFrameReader):
 | |
|   def __init__(self, fn, frame_type, index_data, readahead=False, readbehind=False):
 | |
|     StreamGOPReader.__init__(self, fn, frame_type, index_data)
 | |
|     GOPFrameReader.__init__(self, readahead, readbehind)
 | |
| 
 | |
| 
 | |
| def GOPFrameIterator(gop_reader, pix_fmt):
 | |
|   dec = VideoStreamDecompressor(gop_reader.fn, gop_reader.vid_fmt, gop_reader.w, gop_reader.h, pix_fmt)
 | |
|   yield from dec.read()
 | |
| 
 | |
| 
 | |
| def FrameIterator(fn, pix_fmt, **kwargs):
 | |
|   fr = FrameReader(fn, **kwargs)
 | |
|   if isinstance(fr, GOPReader):
 | |
|     yield from GOPFrameIterator(fr, pix_fmt)
 | |
|   else:
 | |
|     for i in range(fr.frame_count):
 | |
|       yield fr.get(i, pix_fmt=pix_fmt)[0]
 | |
| 
 | |
| 
 | |
| class NumpyFrameReader:
 | |
|   def __init__(self, name, w, h, cache_size):
 | |
|     self.name = name
 | |
|     self.pos = -1
 | |
|     self.frames = None
 | |
|     self.w = w
 | |
|     self.h = h
 | |
|     self.cache_size = cache_size
 | |
| 
 | |
|   def close(self):
 | |
|     pass
 | |
| 
 | |
|   def get(self, num, count=1, pix_fmt="nv12"):
 | |
|     num -= 1
 | |
|     q = num // self.cache_size
 | |
|     if q != self.pos:
 | |
|       del self.frames
 | |
|       self.pos = q
 | |
|       self.frames = np.load(f'{self.name}_{self.pos}.npy')
 | |
|     return [self.frames[num % self.cache_size]]
 | |
| 
 |