[mythtv-users] Increase in recorded file sizes

[Mike Perkins]

John Pilkington wrote:
> Matthew McClement wrote:
>> Mike Perkins wrote:
>>> Gordon McCrae wrote:
>>>> Actually, I've always had this (for the last year) without and now
>>>> with multirec. The BBC streams are higher rates / resolution than
>>>> some other channels. If you play the .mpg file with mplayer, it'll
>>>> tell you the mitrate, resolution etc. I especially notice that
>>>> channels like E4 transmit in some odd resolutions like 540x400 etc,
>>>> depends on the programme, time of day etc.
>>>>
>>> I've only noticed this happening the last two weeks. Is it possible
>>> for different transmitters to offer different bit rates? I'm probably
>>>  grasping at straws, but I'm trying to figure out what's different.
>>>
>>> This only seems to have happened (for me) since the multirec code 
>>> activated itself.
>>
>> Bitrates will vary from transmitter to transmitter and from timeslot 
>> to timeslot. The BBC channels definately have a higher bitrate than 
>> anything else however, as the following bit of atrocious SQL 
>> demonstrates:
>>
>> mysql> SELECT c.callsign, 
>> AVG((r.filesize/1024/1024)/(TIME_TO_SEC(TIMEDIFF(r.progend,r.progstart))/60/60)) 
>> AS MBytePerHour FROM recorded AS r JOIN channel AS c ON r.chanid = 
>> c.chanid  GROUP BY c.callsign ORDER BY MBytePerHour;
>> +-----------+-----------------------+
>> | callsign  | MBytePerHour          |
>> +-----------+-----------------------+
>> | Film4     | 1256.1109891145130000 |
>> | Dave      | 1572.9996911652234762 |
>> | ITV3      | 1788.8391819978370000 |
>> | E4        | 1801.8339177911930000 |
>> | Channel 4 | 2003.3352870941165000 |
>> | ITV1      | 2158.3057354018532692 |
>> | ITV2      | 2166.5138244628910000 |
>> | BBC THREE | 2242.9232841491700000 |
>> | BBC FOUR  | 2881.7079391479490000 |
>> | BBC TWO   | 3006.7467575073240000 |
>> | BBC ONE   | 3155.6208727688140968 |
>> +-----------+-----------------------+
>> 11 rows in set (0.00 sec)
>>
>> (you can get the min and max bitrates for a channel by changing AVG in 
>> the above to MIN or MAX)
>>
>> BBC1 has bitrates that vary from 3GB/hour all the way up to 
>> 4.3GB/hour(!). The high bitrate recordings appear to be Points of 
>> View, bizarrely, with Rachel Allen's Bake making second at 3.5GB/hour.
>>
>> The "Jonathan Creek Christmas Special", as a contrast, only got 
>> 2.7GB/hour on BBC1.
>>
>> Perhaps your regular recordings have gotten a bitrate bump as of late?
>>
>> Matt
> 
> A change in the recording profile is perhaps the most likely cause of a 
> sudden change in recorded bitrate.
> 
> Frontend > Setup > TV settings > Recording Profiles > Hardware DVB 
> Encoders > Default > Recording Type > Normal/TV only/Audio only
> 
> 'Normal' will record interactive stuff as well as the main channel - but 
> maybe only if you have 'interactive TV' enabled in the 'Playback OSD' 
> menu.  These settings might perhaps have got changed in the card-reshuffle?
> 
> I liked the use of SQL here.
I did *nothing* other than delete all cards, assign card 0 and card 2, allocate 
existing Freeview source to card 0 and 2. Changed nothing else at all.

This was card 1 (still in the slot but unallocated) was giving me 50% 
zero-length recordings.

I'm not able to try out your SQL at the moment, but it looks interesting.

-- 

Mike Perkins