Reads the special meta-data in Insta360 "INSV" and "INSP" files.
Inspired by https://github.com/exiftool/exiftool, but without the memory limitations.
Very special thanks to Phil Harvey (https://github.com/boardhead) for the reverse engineering!
"Fun fact": if you didn't know yet, *.insv files are just *.mp4 files with an extra trailer. So, tools like FFMPEG will just extract the raw frames for you.
And *.insp files are readable as *.jpg files, again, with an extra trailer bit.
using InstaTrailer
# to read all trailer data (even unknown types as raw byte data)
records = open("VID_20200929_095645_00_186.insv") do io
extract_trailers(io)
end
# to just read imu data:
imu = read_imu("VID_20200929_095645_00_186.insv")
# also from image data:
imu = read_imu("IMG_20200322_162224_00_173.insp")
# and the exposure/time for all video frames (so you can relate the imu):
exposure = read_exposure("VID_20200929_095645_00_186.insv")
Check out lib\Image\ExifTool\QuickTimeStream.pl in the ExifTool repository to figure out how to decode other meta data types, like I did for ImuData and ExposureData.
Contribute another section in this repo's src/DataTypes.jl, or, if you don't feel like sharing, just overload InstaTrailer.read_data for the TrailerType{0x???} you want to decode, and extract_trailers will also decode that type.
More documentation!
More data types, besides IMU and Exposure. Calibration parameters are up next!