Ideal quality/file size for tv episodes

Off-Topic
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I sit about 2m or 6.5 feet away from my 42" TV (LG LED HD).
I have a decent 76mbs unlimited connection and have noticed that a few episodes had file sizes in excess of 1.5GB and one 3GB.

I understand a bit about video quality, res and compression and that bigger is generally better. Their is also diminishing return for significantly longer download time and storage requirements. Size isn’t everything as source quality, compression and format all play a large role.

In general, for new releases assuming they are encoded with an efficient codec what range will give an ideal viewing experience. As in larger won’t give a perceivably better viewing experience. I’m not really sure what kind of quality is being broadcasted these days as I don’t pay for cable.

I intend to set a max file size in Sonarr for HD quality.
What is recommended for 720 and 1080 files for 42 minute episodes

Is their a guide on recommended settings?
I changed setting from HD-All to HD-720

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Ok, I’ll bite even though this is an extremely difficult question to answer fully… and I’m by no means an expert, so others should correct me where i go wrong.

The primary thing you want to consider is your TV’s capability… Assuming your TV was bought recently enough, it probably supports full 1080p… so that’s the max resolution you should be looking at (anything larger than that will just be wasted on your TV (i.e. 4K downloads are worthless to you).

When you play a 720p video on a 1080p TV the TV will actually scale the 720p video up to 1080p… so this is where quality of TV scaler comes into play.

The next really big question in any quality discussion is the source video frame-rate… To give a brief understanding…

TV is generally aired at 60fps
Movies and TV shows though are generally recorded/published between 24 and 30fps
(the big difference here is because live events like concerts/sports/etc look kind of jerky at 30fps, so they are broadcast at 60fps… meanwhile movies/shows, tend to be fine at 30fps and so are recorded there and when broadcast via tv, frames are doubled to get it up to 60fps for the broadcast standard… there is a push with newer digital recordings and such to record everything directly at 60fps)

Knowing the frame rate and resolution… in your case (assuming a TV show and 720p)… and assuming you are using H.264 codec (pretty much the standard now, though H.265 is coming with potentials for halving file sizes)…

You can calculate the following based on the H.264 base encoding profile (.142 bits/pixel, 1.78 ratio):
1280 x 720 resolution
30 fps
= Bitrate of ~ 3.9Mbps

Once you have a bitrate, it’s simply calculating the bits-per-second times the number of seconds of your show to get the video file size expected…

For example 3.9Mbps * 42min video = ~1.24GB

Doing quick maths and circling this all back… 42 mins of video would be about the following sizes:

720p/30fps = 3.9Mbps = 1.24GB per 42 min show
720p/60fps = 7.9Mbps = 2.49GB per 42 min show
1080p/30fps = 8.9Mbps = 2.8GB per 42 min show
1080p/60fps = 17.8Mbps = 5.6GB per 42 min show
4K/30fps = 35.5Mbps = 11.2GB per 42 min show
4K/60fps = 71.1Mbps = 22.39GB per 42 min show

Anything smaller than these, is doing some kind of compression whether it is variable bitrate encoding or some other mechanism and therefore is less than optimum for those resolutions on your display. (whether they are “ok” to you is obviously a deeply personal opinion)

HOWEVER, there is an IMPORTANT aspect missing here… namely AUDIO…

I’ll spend less time here, as it’s pretty “wild” out there as to what audio qualities are available… however there are some important things to note…

First, a single file (mkv/mp4/etc) can encapsulate MANY audio streams… so you can have mono/stereo/5.1/lossless/etc all inside a single file… each stream obviously has file size, and therefore it increases the size of the overall file the more audio streams you have… Additionally a file can contain multiple languages which may each have multiple quality streams as well… so you can see you can add a TON of file size depending on how many audio streams are embedded in the file… in fact, oftentimes most of the space on a Blu-Ray is audio files if it is an international movie…

To give you some ideas of audio file sizes, here are some of the basics

Typical MP3 stereo = ~128kbps (varies dramatically, 128 is middle of the road) = 40MB per 42 min show
TV broadcast 5.1 = ~448kbps (some are lower, some higher) = 141MB per 42 min show
Dolby Digital 5.1 = 640kbps = 201MB per 42 min show
DTS Digital Surround 5.1 = 1.524Mbps = 480MB per 42 min show
Dolby Digital Plus 7.1 = 4.736Mbps = 1.49GB per 42 min show
Dolby TrueHD (lossless) = 18.64Mbps = 5.87GB per 42 min show
DTS-HD Master Audio (lossless) = 24.5Mbps = 7.72GB per 42 min show

(Note: Dolby & DTS specs were taken from Blu-Ray specification, there are probably other specs too)…

Unfortunately, the “scene”/“uploaders” haven’t really standardized a way to display audio contents for video files yet, so you have to do a bunch of reading of the NFOs of the files you download to figure out what’s in it generally…

All that said… let’s say you assume that there is only a single stream of audio in a file, and you have a 5.1 sound system, and a 720p TV… Then the candidate files you would be looking for would be in the range of:

Dolby 5.1 (201MB) + 720p/30 (1.24GB) = 1.44GB
DTS 5.1 (480MB) + 720p/30 (1.24GB) = 1.72GB

Obviously this is a much longer answer than what you were probably looking for… so if you’re just skimming…

For a 42 min show…
for 720p I would set a minimum of 1GB and max of 4GB (to allow for 60fps or many audio streams)
for 1080p I would set a minimum of 3GB and max of 10GB (to allow for 60fps or many audio streams)

Anything smaller than these minimums has some “extra” compression that is probably degrading the picture quality and so you would want to avoid these unless file-space is your primary concern and you’re less concerned with video quality.

If you have 7.1 sound or want lossless audio and want it in your files… I would suggest looking through files manually to figure out what audio-tracks are included as many commerical Blu-Rays don’t include 7.1 surround yet and most encoders don’t do lossless audio due to filesize…

Hope that helps… feel free to ask follow ups and I’ll try and clarify this post.

Edit 1: Also, subtitles in some formats are included in the file container itself and can therefore add to file size, though usually very small amounts compared to the main audio/video portions.

4 Likes
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Nice, thanks for the very through answer. My set is an LG LED 1080p and only a few months old and a 2.1 set of speakers.
Actually this answer is exactly what I’m looking for but didn’t expect to get.
I can get a general idea online when talking about DVD and Blu-Ray films but I knew little about TV broadcasting standards.

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No problem, the obvious problem with all of this, is that it’s damn near impossible to tell exactly what’s in a container/file without investigating it manually… so when you see a 3GB “720p” file, you don’t really know what’s in it, so for automated downloader purposes it’s really hard to rely on filesize as a determinate of quality.

I’ve often wondered if we could somehow incorporate meta-data like this into the nzb/torrent meta-data somehow so that one could filter/search/restrict based on this kind of thing more accurately.

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It would be idea if tags could be used for individual series so I could require DIMENSION[rarbg] or DIMENSION [eztv] in the file name. Though, I don’t know the difference between eztv and rarbg it would allow for constancy in what it currently a bit of a lottery.

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Tags + Release Restrictions will give you this.

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Think this isn’t entirely fair. something at 60fps is going to be compressed better coz of better motion-compression.
But that’s largely besides the point because you have to look at quality first, not compression ratios, when you make decisions.

@silk186
What do you want? Do you like crisp sharp pictures?
Do you have a good audio set? Audio is 95% of the experience. But you rarely get to choose based on audio.
What can you afford? How much disk space do you have available?
Do you watch and then throw away or do you archive?

Personally I prefer WEB-DL 720p atm over Bluray coz although bluray is better quality but more than twice the size.
The best 1080p Bluray episodes (45min) can be 5gb easy.

If you download, watch and then delete and have no internet cap. go for quality, if there wasn’t a reason, the scene wouldn’t encode em at 5gb.
If you intend to keep it, but have decent space, set the limit on bluray a bit lower so you get the smaller blurays or go for 720p.

But don’t go too low for 1080p. It’s better to have a 2.0gb 720p bluray than a 2.0gb 1080p bluray.

For recent stuff there isn’t bluray, pick either HDTV-1080p or WEBDL-720p, use WEBDL-1080p only if nothing else is available.

I can’t emphasis enough: resolution is not quality.
If you see a 2h movie at 1080p for less than 4.0GB, it will be horrible, and that’s conservative. There are absolutely horrible 2 GB movie encodes out there claiming awesome “FullHD” quality. :rage:

Except for certain animation, those compress significantly better. Think I got a pretty good 2.5gb encode of The Secret World of Arrietty lying around. I must have encoded that one at least 3 times with different settings to compare :smile:

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I’m a grad student paying non-EU tuition so I don’t have a great set-up but it’s OK.
I have an LG 42" LED TV (LG 42LB5500) and Microlab FC360 2.1 Speakers so I don’t need DTS 5.1 audio.
My TV is 42" and my viewing distance is 2m (6.5 feet). I have 6TB of disk space and I delete shows after I watch them so space isn’t really an issue. I’m thinking since my TV is on the small side that WEB-DL 720p would be ideal.

I understand about resolution vs compression but have very limited experience encoding myself.

Without encoding a Blu-Ray in different levels of compression and resolution myself I don’t have a way reliable to compare. Hopefully h.265 will pick up quickly. A few searches brings up very little content. Actually, searching a bit more little TV content comes up in files larger than 1.7GB for many series. Some have nothing seeded over 400MB for half hour shows. This is one of the other problems in setting larger file requirements, very large files lack seeders, significantly increasing download times.

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Thanks, I will look into how to set this up. I didn’t realise the tags could function in this way

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Ah, I was assuming usenet, then big files rarely matter :smile:

At 2m a 42inch is pretty big tbh. but it’s easy to try, download a WEBDL-720p, Bluray-720p and 1080p and check it out.