Recordings have missing frames, yet no errors in log

[CX23882-19]

I've been experiencing an issue with some DVB-S (Freesat, UK) recordings which only seems to occur when recording from "ITV1 West Country". ITV1 West Country is unique among all of the other Freesat channels in that the bitrate is around 6-7Mbps compared to a more typical 3Mbps and it is the only channel I am having this problem with.

 

My problem is, I schedule a recording via the DVBViewer Recording Service, writing in TS format. Once the recording has finished I take a look at the log file and see that there are zero discontinuities, or perhaps a couple just as the recording starts. From this I assume that the recording is perfect.

 

However... when watching the recordings in any player (VLC, MPC-HC, ZoomPlayer) I see glitches at various points. Not really bad ones, just a slightly jump, but they're there. If I run the recording through VideoReDo, I see "Missing temporal reference" errors (followed by "Temporal frame drop") at those points in the file.

 

For example:

 

2009-10-18 21:16:49 Program Information

File Name: E:\Video\Recorded TV\Films\09-12_23-25-06_ITV1 W Country_The Whole Nine Yards.ts

File Size: 7170286160 ( 6.68 GB )

Program Duration: 01:59:52.17

File Type: TS Stream

Encoding: MPEG2

Video stream Id: 3344 (xD10)

Encoding Dimensions: 704 x 576

Display Size: 704 x 576

Aspect Ratio: 16:9

Frame Rate: 25.00 FPS

Bit Rate: 10.000 Mbps

VBV_Buffer: 224 KB

Profile: Main/Main

Progressive: Prog or Int

Chroma: 4:2:0

Audio Format: Layer 2

Audio Stream Id: 3345 (xd11)

Audio Bit Rate: 192 Kbps

Audio Sampling Rate: 48000 Hz

TS Mux Rate (bps): 4599402

 

2009-10-18 21:16:49 Starting new Frame Accurate Output Segment: start:0.000 (00:00:00.00), end:10792680.011 (02:59:52.17)

2009-10-18 21:18:35 Missing temporal reference(s) at frame 6 : 00:55:28.24

2009-10-18 21:19:07 Missing temporal reference(s) at frame 10 : 01:13:22.21

2009-10-18 21:19:23 Missing temporal reference(s) at frame 10 : 01:20:24.07

2009-10-18 21:19:45 Temporal frame drop, at: 01:29:18.20, originalPTS: 5358800.01 (01:29:18.20), frame type: 2, temporal: 7 (7)

2009-10-18 21:19:45 Temporal frame drop, at: 01:29:18.20, originalPTS: 5358960.01 (01:29:18.24), frame type: 2, temporal: 11 (7)

2009-10-18 21:19:45 Temporal frame drop, at: 01:29:18.20, originalPTS: 5358840.01 (01:29:18.21), frame type: 3, temporal: 8 (3)

2009-10-18 21:19:45 Temporal frame drop, at: 01:29:18.20, originalPTS: 5358880.01 (01:29:18.22), frame type: 3, temporal: 9 (3)

2009-10-18 21:19:45 Temporal frame drop, at: 01:29:18.20, originalPTS: 5358920.01 (01:29:18.23), frame type: 3, temporal: 10 (3)

2009-10-18 21:19:45 Missing temporal reference(s) at frame 4 : 01:29:18.20

2009-10-18 21:19:45 Unable to find a frame to add. Remooving an audio frame instead

2009-10-18 21:19:45 Resync: removed 1 audio frames, at audio 01:29:18.20, original (01:29:18.15), sync changed from 346.99 to 186.99

2009-10-18 21:19:45 Resync: added 5 video frames, at video 01:29:19.00, original (01:29:19.04), sync changed from 346.99 to 186.99

2009-10-18 21:19:45 Resync: added 3 video frames, at video 01:29:19.15, original (01:29:19.16), sync changed from 202.99 to 42.99

2009-10-18 21:20:42 Output complete. Input file: E:\Video\Recorded TV\Films\09-12_23-25-06_ITV1 W Country_The Whole Nine Yards.ts

Output file: D:\Video\Downloads\Films\09-12_23-25-06_ITV1 W Country_The Whole Nine Yards.mpg

Mode: Frame Accurate

-Video output packets: 3364687

-Audio output packets: 170914

-Padding output packets: 0

Video output frames: 179815

Audio output frames: 299690

Processing time (secs): 233

Processed frames/sec: 771.67

Actual Video Bitrate: 7.56 Mbps

* Input Sequence Errors: 9

* Video resync frames added: 8

* Audio resync frames removed: 1

 

Has anybody else seen this happening? I assumed that if DVBViewer is reporting zero discontinuities, I'm getting perfect reception of the TS. Is that a wrong assumption?

 

Is it possible that something is happening during the file writing stage? Or could it be that the actual streams are corrupt as broadcast?

 

Edit: It seems that something odd is going on with the PTS timecodes: 01:29:18.20, 01:29:18.24, 01:29:18.21, 01:29:18.22, 01:29:18.23. What would make it jump from 20 to 24 and then carry on as normal?

Edited October 18, 2009 by CX23882-19