MPEG TS Streams missing LFE channel ?

[s1lenc0r]

I recently started to watch the series Spartacus - Blood and Sand.

I currently have episodes 1 to 6 in 1080i ts transport stream.

When opening in Media info, the 1st and 2nd episode show as having 6 channels, while episodes 3-6 contain only 5 channels (missing the lfe channel)?

Is this correct, or is it a malfunction in Mediainfo ?

Is there someone with a logical explanation for this problem ?

Here is the info Mediainfo gives about these 6 files

eneral
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E01.srt
Format : SubRip
File size : 28.4 KiB

Text
Format : SubRip

General
ID : 1
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E01.ts
Format : MPEG-TS
File size : 6.18 GiB
Duration : 52mn 43s
Overall bit rate : 16.8 Mbps

Video
ID : 33 (0x21)
Menu ID : 1 (0x1)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High
Format settings, BVOP : Yes
Format settings, Matrix : Default
Format_Settings_GOP : M=3, N=15
Duration : 52mn 43s
Bit rate mode : Variable
Bit rate : 15.2 Mbps
Nominal bit rate : 17.6 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.245
Stream size : 5.61 GiB (91%)

Audio
ID : 36 (0x24)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 52mn 43s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Stream size : 145 MiB (2%)

Text
ID : 33 (0x21)608-1
Menu ID : 1 (0x1)
Format : EIA-608
Muxing mode : MPEG Video / EIA-708
Muxing mode, more info : Muxed in Video #1
Duration : 52mn 43s
Stream size : 0.00 Byte (0%)

General
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E02.srt
Format : SubRip
File size : 32.7 KiB

Text
Format : SubRip

General
ID : 1
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E02.ts
Format : MPEG-TS
File size : 6.05 GiB
Duration : 51mn 13s
Overall bit rate : 16.9 Mbps

Video
ID : 33 (0x21)
Menu ID : 1 (0x1)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High
Format settings, BVOP : Yes
Format settings, Matrix : Default
Duration : 51mn 13s
Bit rate mode : Variable
Bit rate : 15.3 Mbps
Nominal bit rate : 17.6 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Resolution : 8 bits
Colorimetry : 4:2:0
Bits/(Pixel*Frame) : 0.247
Stream size : 5.49 GiB (91%)

Audio
ID : 36 (0x24)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 51mn 13s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Stream size : 141 MiB (2%)

Text #1
ID : 33 (0x21)608-0
Menu ID : 1 (0x1)
Format : EIA-608
Muxing mode : MPEG Video / EIA-708
Muxing mode, more info : Muxed in Video #1
Duration : 51mn 13s
Stream size : 0.00 Byte (0%)

Text #2
ID : 33 (0x21)1
Menu ID : 1 (0x1)
Format : EIA-708
Muxing mode : MPEG Video / EIA-708
Muxing mode, more info : Muxed in Video #1
Duration : 51mn 13s
Stream size : 0.00 Byte (0%)

General
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E03.srt
Format : SubRip
File size : 34.9 KiB

Text
Format : SubRip

General
ID : 1
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E03.ts
Format : MPEG-TS
File size : 5.28 GiB
Duration : 54mn 9s
Overall bit rate : 14.0 Mbps

Video
ID : 33 (0x21)
Menu ID : 1 (0x1)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High
Format settings, BVOP : Yes
Format settings, Matrix : Default
Format_Settings_GOP : M=3, N=15
Duration : 54mn 9s
Bit rate mode : Variable
Bit rate : 12.6 Mbps
Nominal bit rate : 13.2 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Standard : NTSC
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.203
Stream size : 4.77 GiB (90%)

Audio
ID : 36 (0x24)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 54mn 9s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 5 channels
Channel positions : Front: L C R, Side: L R
Sampling rate : 48.0 KHz
Stream size : 149 MiB (3%)

General
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E04.srt
Format : SubRip
File size : 30.7 KiB

Text
Format : SubRip

General
ID : 1
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E04.ts
Format : MPEG-TS
File size : 4.60 GiB
Duration : 47mn 11s
Overall bit rate : 14.0 Mbps

Video
ID : 33 (0x21)
Menu ID : 1 (0x1)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High
Format settings, BVOP : Yes
Format settings, Matrix : Default
Format_Settings_GOP : M=3, N=15
Duration : 47mn 11s
Bit rate mode : Variable
Bit rate : 12.6 Mbps
Nominal bit rate : 13.2 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Standard : NTSC
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.203
Stream size : 4.16 GiB (90%)

Audio
ID : 36 (0x24)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 47mn 11s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 5 channels
Channel positions : Front: L C R, Side: L R
Sampling rate : 48.0 KHz
Stream size : 130 MiB (3%)

General
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E05.srt
Format : SubRip
File size : 35.7 KiB

Text
Format : SubRip

General
ID : 1
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E05.ts
Format : MPEG-TS
File size : 5.20 GiB
Duration : 53mn 17s
Overall bit rate : 14.0 Mbps

Video
ID : 33 (0x21)
Menu ID : 1 (0x1)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High
Format settings, BVOP : Yes
Format settings, Matrix : Default
Duration : 53mn 16s
Bit rate mode : Variable
Bit rate : 12.6 Mbps
Nominal bit rate : 13.2 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Standard : NTSC
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.203
Stream size : 4.69 GiB (90%)

Audio
ID : 36 (0x24)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 53mn 16s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 5 channels
Channel positions : Front: L C R, Side: L R
Sampling rate : 48.0 KHz
Stream size : 146 MiB (3%)

General
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E06.srt
Format : SubRip
File size : 50.0 KiB

Text
Format : SubRip

General
ID : 1
Complete name : G:\Series 1080\Spartacus Blood and Sand 1080i\Season 01\Spartacus Blood and Sand - S01E06.ts
Format : MPEG-TS
File size : 5.07 GiB
Duration : 51mn 58s
Overall bit rate : 14.0 Mbps

Video
ID : 33 (0x21)
Menu ID : 1 (0x1)
Format : MPEG Video
Format version : Version 2
Format profile : Main@High
Format settings, BVOP : Yes
Format settings, Matrix : Default
Format_Settings_GOP : M=3, N=15
Duration : 51mn 57s
Bit rate mode : Variable
Bit rate : 12.6 Mbps
Nominal bit rate : 13.2 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Standard : NTSC
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.203
Stream size : 4.58 GiB (90%)

Audio
ID : 36 (0x24)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 51mn 57s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 5 channels
Channel positions : Front: L C R, Side: L R
Sampling rate : 48.0 KHz
Stream size : 143 MiB (3%)

NOTE: I use a script to rename the files and subtitles.

[guns1inger]

Many 5.1 mixes for domestic use don't have an LFE, or if they do, it is empty. This is not true for all, but it is for many. The reason they don't is because the cut over for most domestic amps is set at a level whereby the bass tones in the normal channel sis enough to trigger the sub woofer, and therefore an LFE channel is superfluous.

Of course without knowing where these came from, it is hard to say why they are the way they are. If you downloaded them they may have been created by someone who simply screwed up.

[s1lenc0r]

Let's say I want to convert these files to a more convenient format, including various subtitles, like mkv.

Is there a way to convert the audio to 5.1 channel ac3 ?

[guns1inger]

You gain nothing and risk a quality drop through re-encoding. I would just use what you have.