def __data_generation(self, seVideo: pd.Series) -> (np.array(float), int):
"Returns frames for 1 video, including normalizing & preprocessing"
# Get the frames from disc
ar_nFrames = files2frames(seVideo.sFrameDir)
#print(ar_nFrames.shape)
#scipy.misc.imsave('outfile.jpg', ar_nFrames[0])
#scipy.misc.imsave('outfile_flip.jpg', np.fliplr(ar_nFrames[0]))
ar_nFrames_flip = np.array(
[np.fliplr(ar_nFrames[i]) for i in range(ar_nFrames.shape[0])])
# only use the first nChannels (typically 3, but maybe 2 for optical flow)
ar_nFrames = ar_nFrames[..., 0:self.nChannels]
ar_nFrames_flip = ar_nFrames_flip[..., 0:self.nChannels]
ar_nFrames = images_normalize(ar_nFrames,
self.nFrames,
self.nHeight,
self.nWidth,
bRescale=True)
ar_nFrames_flip = images_normalize(ar_nFrames_flip,
self.nFrames,
self.nHeight,
self.nWidth,
bRescale=True)
self.prv_frame = ar_nFrames
self.prv_frame_flip = ar_nFrames_flip
return ar_nFrames, seVideo.nLabel, ar_nFrames_flip, seVideo.nLabel
def __data_generation(self, seVideo:pd.Series) -> (np.array(float), int):
"Returns frames for 1 video, including normalizing & preprocessing"
# Get the frames from disc
ar_nFrames = files2frames(seVideo.sFrameDir)
# only use the first nChannels (typically 3, but maybe 2 for optical flow)
ar_nFrames = ar_nFrames[..., 0:self.nChannels]
ar_fFrames = images_normalize(ar_nFrames, self.nFrames, self.nHeight, self.nWidth, bRescale = True)
return ar_fFrames, seVideo.nLabel
def framesDir2flowsDir(sFrameBaseDir:str, sFlowBaseDir:str, nFramesNorm:int = None, sAlgorithm:str = "tvl1-fast"):
""" Calculate optical flow from frames (extracted from videos)
Input videoframe structure:
... sFrameDir / train / class001 / videoname / frames.jpg
Output:
... sFlowDir / train / class001 / videoname / flow.jpg
"""
# do not (partially) overwrite existing directory
#if os.path.exists(sFlowBaseDir):
# warnings.warn("\nOptical flow folder " + sFlowBaseDir + " alredy exists: flow calculation stopped")
# return
# get list of directories with frames: ... / sFrameDir/train/class/videodir/frames.jpg
sCurrentDir = os.getcwd()
os.chdir(sFrameBaseDir)
liVideos = sorted(glob.glob("*/*/*"))
os.chdir(sCurrentDir)
print("Found %d directories=videos with frames in %s" % (len(liVideos), sFrameBaseDir))
# loop over all videos-directories
nCounter = 0
for sFrameDir in liVideos:
# generate target directory
sFlowDir = sFlowBaseDir + "/" + sFrameDir
if nFramesNorm != None and os.path.exists(sFlowDir):
nFlows = len(glob.glob(sFlowDir + "/*.*"))
if nFlows == nFramesNorm:
print("Video %5d: optical flow already extracted to %s" % (nCounter, sFlowDir))
nCounter += 1
continue
else:
print("Video %5d: Directory with %d instead of %d flows detected" % (nCounter, nFlows, nFramesNorm))
# retrieve frame files - in ascending order
arFrames = files2frames(sFrameBaseDir + "/" + sFrameDir)
# downsample
if nFramesNorm != None:
arFrames = frames_downsample(arFrames, nFramesNorm)
# calculate and save optical flow
print("Video %5d: Calc optical flow with %s from %s frames to %s" % (nCounter, sAlgorithm, str(arFrames.shape), sFlowDir))
arFlows = frames2flows(arFrames, sAlgorithm = sAlgorithm)
flows2file(arFlows, sFlowDir)
nCounter += 1
return
