this IS season 4. other uploaders ar miss-naming these episodes. check BBC Iplayer for confirmation


https://www.imdb.com/title/tt3815412



Format : MPEG-4
Format profile : Base Media
Codec ID : isom (isom/iso2/avc1/mp41)
Overall bit rate mode : Variable
Overall bit rate : 1 658 kb/s



Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : [email protected]
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Format settings, GOP : M=8, N=96
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 57 min 38 s
Bit rate : 1 559 kb/s
Width : 960 pixels
Height : 540 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.120
Stream size : 643 MiB (94%)
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
Codec configuration box : avcC

Audio
ID : 2
Format : AAC LC SBR
Format/Info : Advanced Audio Codec Low Complexity with Spectral Band Replication
Commercial name : HE-AAC
Format settings : Implicit
Codec ID : mp4a-40-2
Duration : 57 min 38 s
Bit rate mode : Variable
Bit rate : 96.0 kb/s
Maximum bit rate : 97.9 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 23.438 FPS (2048 SPF)
Compression mode : Lossy
Stream size : 39.6 MiB (6%)
Language : English
Default : Yes
Alternate group : 1