解碼compressedDepth
的正確方法是首先從原始數據中刪除標題,然後轉換剩餘的數據。
這記錄在image_transport_plugins/compressed_depth_image_transport/src/codec.cpp。 在我的機器上,標題大小爲12個字節。這可能會在其他體系結構上有所不同,因爲枚舉的大小沒有定義。
下面的Python代碼片段壓縮16UC1出口和32FC1深度圖像爲PNG文件:
# 'msg' as type CompressedImage
depth_fmt, compr_type = msg.format.split(';')
# remove white space
depth_fmt = depth_fmt.strip()
compr_type = compr_type.strip()
if compr_type != "compressedDepth":
raise Exception("Compression type is not 'compressedDepth'."
"You probably subscribed to the wrong topic.")
# remove header from raw data
depth_header_size = 12
raw_data = msg.data[depth_header_size:]
depth_img_raw = cv2.imdecode(np.fromstring(raw_data, np.uint8), cv2.CV_LOAD_IMAGE_UNCHANGED)
if depth_img_raw is None:
# probably wrong header size
raise Exception("Could not decode compressed depth image."
"You may need to change 'depth_header_size'!")
if depth_fmt == "16UC1":
# write raw image data
cv2.imwrite(os.path.join(path_depth, "depth_" + str(msg.header.stamp) + ".png"), depth_img_raw)
elif depth_fmt == "32FC1":
raw_header = msg.data[:depth_header_size]
# header: int, float, float
[compfmt, depthQuantA, depthQuantB] = struct.unpack('iff', raw_header)
depth_img_scaled = depthQuantA/(depth_img_raw.astype(np.float32)-depthQuantB)
# filter max values
depth_img_scaled[depth_img_raw==0] = 0
# depth_img_scaled provides distance in meters as f32
# for storing it as png, we need to convert it to 16UC1 again (depth in mm)
depth_img_mm = (depth_img_scaled*1000).astype(np.uint16)
cv2.imwrite(os.path.join(path_depth, "depth_" + str(msg.header.stamp) + ".png"), depth_img_mm)
else:
raise Exception("Decoding of '" + depth_fmt + "' is not implemented!")
你不介意分享你有什麼這麼遠嗎? –
第43行改爲「/ camera/depth_registered/image_raw/compressedDepth;」 第57行更改爲 「image_np = cv2.imdecode(np_arr,cv2.CV_LOAD_IMAGE_GRAYSCALE);」 除數據外,刪除了「功能」和「重新發布部分」。其他一切都是一樣的。 – Pototo