Is there such thing as "AVCHD Shrink"

[spapakons]

Hello!

I remember when creating DVDs back in the day, miscalculated the bitrate and the resulting VIDEO_TS folder was over 4480MB, I could use a utility called DVD Shrink to make the folder fit exactly in a blank single layer DVD+R or DVD-R.

I now have the same issue creating AVCHD content. If I miscalculate the bitrate the resulting AVCHD folder might be larger than the capacity of the blank disc. When burning DVDs with Nero Burning ROM I could enable the overburn feature, set the limit to 4500MB and let Nero fit as much of the video as possible. If the VIDEO_TS folder was a little over the disc capacity, I usually missed some seconds from the end credits of the movie, who cares. However if I do the same when burning an AVHCD-DVD disc it won't play at all, so it is essential to make the AVHCD folder as close as possible to the disc capacity. I don't want to make it too small and potentially lose quality, nor I want to exceed the disc capacity. In VirtualDub I would reencode the movie from the original file with less bitrate and make it fit, but I would spend hours to do so because it has no hardware acceleration. In Handbrake or Fastflix (with NVEnc acceleration) unfortunately decreasing the bitrate by a small amount makes no difference on the final size of the video. Decreasing it too much it produces a smaller video than desirable potentially affecting quality.

That's why I would like to use a similar utility to DVD Shrink for AVCHD. Is there any application that can take an AVCHD folder and make it as close as possible to the target size? Is there such thing as "AVCHD Shrink"?

[spapakons]

I guess there isn't any as convenient utility for AVCHD as was DVD Shrink for DVD movies. However, if you know something more, please reply!

Thanks.

[Sharc]

BD Rebuilder

[spapakons]

Thank you! I will download it and try it to see how good it is.

[spapakons]

Well it works much like DVD Shrink. It tries to fit the video on the target size. In my system I have two choices of encoders, either x264/x265 or NVEnc thanks to my nVidia graphics card. The x264/x265 option fails while encoding for some reason. The NVEnc works very fast but as with other CUDA accelerated encoders it is not very accurate. For example, I did one test using a deliberately huge AVCHD folder (9GB) and selected to fit it in 4480MB custom size (the empty space of a DVD-R disc). I expected the resulting AVCHD folder being close to 4.37GB (4480MB), but it was 4.12GB. I increased the target size to 4500MB and it became 4.33GB Better, but I would like the accuracy of DVD Shrink that did the DVD folder as close as possible to 4480MB. I know this is because of the NVEnc, probably x264 would be more accurate, but it fails for some reason. Thanks anyway.

[Sharc]

Learn how to use BD Rebilder. It has a learning curve. For more accurate file size you should use 2-pass encoding rather than CRF encoding. Keep in mind that BD Rebilder can shrink Blurays of say 50GB filesize to 9GB, so it has to reencode the video which is much more complex and demanding than what DVD shrink does, and gives much higher quality at high compression factors than DVDShrink.
Anyway you may take a look at the BD Rebuilder thread over at doom9, with lot of experienced users who may provide help for your questions.
https://forum.doom9.org/showthread.php?t=143716

For your purpose there migt be simpler tools though, without menu features etc.

[spapakons]

Like I said you cannot go exactly to the size you want with a hardware encoder, is a hit and miss. If you are close to the target (say 4.34GB instead of 4.37GB), trying to give a little more bitrate you get the SAME file size for some weird reason. Giving too much bitrate you get a larger file, such as 4.40GB which doesn't fit on a blank DVD. Similarly, if you exceed the target by little (say 4496MB instead of 4480MB), giving a little less bitrate you get the SAME file size, if you give too less you get much smaller size, say 4.25GB which is frustrating. The only way it would be more accurate it would be if done without hardware acceleration. That means instead of NVenc to choose x264/x265. As already said, this doesn't work for me, I get an encoding error, so my only choice is NVEnc with its less than ideal accuracy. The alternative is to use VirtualDub to reencode the movie from the original adjusting the bitrate as necessary but spending many hours to complete.

PS: A workaround for very small size difference (eg 4496 to 4480) is to use MKVToolnix to trim the end of the movie (usually creadits) by a few seconds. The smaller file will fit exactly on 4480MB when processed by MultiAVCHD. But I would prefer if I can avoid trimming the movie.

[El Heggunte]

.........The x264/x265 option fails while encoding for some reason.
...........
That means instead of NVenc to choose x264/x265. As already said, this doesn't work for me, I get an encoding error,

Please tell us, WHAT "encoding error", exactly,

Well it works much like DVD Shrink.

Nope, it doesn't. DVD Shrink does not recompress the video stream(s), whereas BD Rebuilder does.

[spapakons]

I don't remember exactly what the error was, but along the lines "could not find encoder" or something. I said it works much like DVD Shrink in the sense that you have an oversized AVCHD and you shrink it to fit to the target. That doesn't mean necessarily they work the same way. The point is, BR Rebuilder does its job as long as there is a suitable bitrate to use that creates the new AVCHD folder close to the target size. If there isn't any, then the result will be too short (such as 4.25GB or less with target 4.37GB) or oversized and won't fit. You cannot adjust the bitrate in small steps with a hardware encoder like you do with a software equivalent. So it is partly useful. If the resulting AVCHD folder is too small I have either to accept it (I don't) or recreate the AVI intermediate file from the original video in VirtualDub using the x264 or x264vfw codec and calculating the bitrate like

new_bitrate = (4480/AVCHD_size)*old_bitrate

I round this down to the closest 10, such as 6545 rounded to 6540, and this always works to create the appropriate size of the intermediate AVI file. I then import this file in MultiAVCHD to create the AVCHD folder without reencoding of the movie.
My problem is that this procedure requires considerable time, that's why I was looking for an "AVCHD Shrink" application like BD Rebuilder. Thank you for pointing me to it anyway.

[Alwyn]

DVD Shrink does not recompress the video stream(s)

Of course it does. You can get it to shrink to fit a disk eg a DL disk to a single layer disk, or you can rip the movie without encoding eg 6.5GB DL DVD to a 6.5GB MPEG file.

[spapakons]

DVD Shrink used software to reencode the movie and make it fit to 4480MB or whatever was the target. For small compression (such as 90% or more of the original size) you wouldn't notice the difference. BD Rebuilder tries to do the same but sadly software compression (x264/x265) that would be more accurate doesn't work in my case. So I use NVEnc with its less-than-ideal accuracy.

[spapakons]

I now do a new conversion. This time I chose x264/x265 encoders but with Auto quality setting (previously I tried to force highest quality). It now seems to work as expected, no errors yet. Probably the highest quality I was trying to set wasn't compatible with the x264 encoder. Let's see what happens and how good the result is. I will post back.

EDIT: Spoke too soon... It failed again. I copy-paste the log if you can make anything out of it. Why it fails? How to fix it? Thanks!

[07/31/24] BD Rebuilder v0.62.04
[10:47:01] Source: AVCHD
- Input BD size: 4,39 GB
- Approximate total content: [01:37:03.609]
- Target BD size: 4,38 GB
- Windows Version: 6.2 [9200]
- Auto Quality: High Quality (Default), 1-Pass VBR
- Decoding/Frame serving: DirectShow
- Audio Settings: AC3=0 DTS=0 HD=0 Kbs=192
[10:47:01] PHASE ONE, Encoding
- [10:47:01] Processing: VID_00000 (1 of 2)
- [10:47:01] Extracting A/V streams [VID_00000]
- [10:48:41] Reencoding video [VID_00000]
- Source Video: MPEG-4 (AVC), 1280x720
- Rate/Length: 23,976fps, 125.522 frames
- Bitrate: 5.627 Kbs
- [10:48:41] Reencoding: VID_00000, Pass 1 of 1
- Encode failed. Aborting.
- BD-Rebuilder v0.62.04
- Windows Version: 6.2 [9200]
- Working Path Free Space: 594,08GB
- AVISYNTH Version: 3.7.3.0, not recommended version
- LAVFILTERS: Ok
- AnyDVD Remove Annoying Adverts: Incompatible
- X264: Ok
- X265: Ok
- AFTEN: Ok
- FAAC: Ok
- MP4BOX: Ok
- WAVI: Ok
- TSMUXER: Ok
- FRIMEncode: Ok
- FRIMDecode: Ok
[10:49:02] - Failed video encode, aborted

Why AviSynth 3.7.3 is not the recommended version? It is the latest! Should I install 2.6? I wouldn't like to break functionality for other applications.

[El Heggunte]

DVD Shrink does not recompress the video stream(s)

Of course it does. You can get it to shrink to fit a disk eg a DL disk to a single layer disk, or you can rip the movie without encoding eg 6.5GB DL DVD to a 6.5GB MPEG file.

Evidently we are not speaking the same language.

https://www.digitalfaq.com/forum/dvd-copy/2177-how-transcoding-mpeg.html

[spapakons]

I don't care about if DVD Shrink recompresses or not the video to make it fit (sure it does, it doesn't get smaller by magic). What about my issue? Why I get an error when using software encoders x264/x265? They would produce a more accurate result than the hardware encoder NVEnc. In this case approximating the target size is more important than speed.

[johns0]

Dvdshrink doesn't recompress,it takes out data and it looks really crappy with dvds that need to be shrunk at around 60%.

[spapakons]

Dvdshrink doesn't recompress,it takes out data and it looks really crappy with dvds that need to be shrunk at around 60%.

This might be true if the target is 96%-99% of the original size. For smaller sizes it does compression. If you do deep analysis (aka dual pass) the quality is very good so your won't notice any difference for as small as 70% of the original folder. If the original is not DVD-9 (dual layer) disk, and you simply miscalculated the bitrate and the folder is up to 4500MB, DVD Shrink does a really good job shrinking the folder to 4480MB so it fits on a blank single layer disc.

However, what did I tell you? The point is not whether DVD Shrink compresses or not the video. We shouldn't argue about that. The question is what this annoying error message means in BD Rebuilder. Why it fails when I select x264/x265 encoders? How can I fix it? Please reply to these questions, not what DVD Shrink does and what it doesn't. Let me know better, I have used DVD Shrink for many years. Yes, it DOES recompress the video when necessary (not always).

[davexnet]

Do you have the LAV filter active for H.264 (AVC) ?

[spapakons]

DVD Shrink does not recompress the video stream(s)

Of course it does. You can get it to shrink to fit a disk eg a DL disk to a single layer disk, or you can rip the movie without encoding eg 6.5GB DL DVD to a 6.5GB MPEG file.

Evidently we are not speaking the same language.

https://www.digitalfaq.com/forum/dvd-copy/2177-how-transcoding-mpeg.html

This data redundancy is used in DVD Shrink when the target size is close to the original. In layman terms, when you miscalculated the bitrate during authoring your own DVD and the original folder is about 4500MB or less. Using DVD Shrink to fit that on a blank DVD disc of 4480MB (4483MB for DVD+R or 4489MB for DVD-R, I prefer the DVD+R version because they were more compatible with consumer DVD players back in the day. Only Pioneer players favored DVD-R, most other players played DVD+R without any issue) usually exploits redundancy and doesn't recompress the video. However when trying to fit a DVD-9 (dual layer aka up to 8150MB disc) to a DVD-5 blank (aka 4480MB), then redundancy is not enough and recompression of the movie is required. The result is CRAP if you do a quick processing (aka single pass). You must do a deep analysis (aka dual pass) to get as better quality as possible. Back in the day to make the movie as good as possible, we heavily compressed all extras and menus to leave more space for the main movie. Anyone that has used DVD Shrink more than a couple of times knows what I am talking about. To summarize, the "crap" quality you may have seen using DVD Shrink it is not because it just removes more data to make the movie fit, it is because it did a single pass MPEG2 compression which for the technology of the era was guaranteed to produce crap quality. We did dual pass encoding and still quality wasn't always good if compression was to heavy, imagine doing single pass.

BACK TO TOPIC: Please help me understand what the error message in BD Rebuilder means (see my older post) and how to fix it. Stop arguing about how good DVD Shrink was. It was way better than commercial alternatives such as Nero Recode. There is no comparison. If you have use it only a couple of times, then don't judge it! You clearly misused it and you don't know what you are talking about.

[Sharc]

Yes, it DOES recompress the video when necessary (not always).

Just stop now justifying some wording nonsense. Compression by re-encoding (BD Rebuilder) is a complex process involving decompression of the source followed by the full process of h.264 AVC or h.265 encoding for recompression. DVD Shrink operates on one aspect of the process only: The quantization. It increases the quantizer of the mpeg2 source in order to reduce the filesize. Sometimes it is called re-quant. Works for moderate size reduction, produces inferior results for larger reduction. If you don't see the difference .... oh well.
You don't know what you don't know.

(Btw. Nero Recode and DVD Shrink have the same Daddy, as far as i remember )

Your BD Rebuilder log:
- AnyDVD Remove Annoying Adverts: Incompatible

[El Heggunte]

OK, I pasted « https://www.google.com/search?q=%22bd+rebuilder%22+%22Encode+failed.+Aborting%22 » onto the false god Gluegow, and...

well, BD Rebuilder apeears to be VERY "picky", to say the least.

Various possible causes...
*** "incorrect" Avisynth version (but don't ask me why);
*** source files are better (?) when available on the HDD, not while they are being decrypted by AnyDVD
*** etc

Also, I had no idea BD Rebuilder still depends on outdated software like Aften and faac.

[spapakons]

Do you have the LAV filter active for H.264 (AVC) ?

If you mean if I have chosen LAV Filter for H264 in Preferred Decoders section of K-Lite settings, no I have set that to FFDshow. Should I set it to LAV Filter? Will it make any difference? I will try it.

EDIT: Didn't make any difference. Similar log (see my older post), "Failed video encode", "AviSynth 3.7.3.0 is not recommended version" Any Ideas? It might work with AviSynth 2.6 but if that means I compromize functionality for other applications, no thanks! I rather manually recompress the original video and reauthore it with MultiAVCHD. Such a pity, BD Rebuilder looked like a good solution...

[Sharc]

"AviSynth 3.7.3.0 is not recommended version" Any Ideas?

That's just a hint. The author does not test BD Rebuilder with every update of avisynth filters. So the ultimate responsibility of not using the recommended version is with the user.
(I am more sceptical that something got possibly messed up with your K-lite codec pack).

[spapakons]

Yes, it DOES recompress the video when necessary (not always).

Just stop now justifying some wording nonsense. Compression by re-encoding (BD Rebuilder) is a complex process involving decompression of the source followed by the full process of h.264 AVC or h.265 encoding for recompression. DVD Shrink operates on one aspect of the process only: The quantization. It increases the quantizer of the mpeg2 source in order to reduce the filesize. Sometimes it is called re-quant. Works for moderate size reduction, produces inferior results for larger reduction. If you don't see the difference .... oh well.
You don't know what you don't know.

(Btw. Nero Recode and DVD Shrink have the same Daddy, as far as i remember )

Your BD Rebuilder log:
- AnyDVD Remove Annoying Adverts: Incompatible

How can you be so sure? Have you seen the source code? When re-quant is not sufficient to create the target size from a large DVD-9 source (over 6GB) then it must use compression. It cannot remove data forever, there is a limit. When this limit is reached it must re-encode the video to keep acceptable quality (or be viewable at all). Common Sense. That exactly makes DVD Shrink very fast for small target difference (95-99% of the original size) and that's why it takes more time when the difference is larger. That's exactly why the result is crap if you rely on single pass shrinking and you don't activate deep analysis (aka dual pass). Back in the day with our humble Pentium 4 computers it might take 2-3 hours to shrink a DVD-9 movie to DVD-5 using deep analysis, but it was certainly worth it. Much preferable than finishing at half or less time (without deep analysis aka single pass) only to see the result was full of artifacts and blocking. With today's much faster computers deep analysis takes half an hour or less, so one would be idiot not to enable it.

[spapakons]

"AviSynth 3.7.3.0 is not recommended version" Any Ideas?

That's just a hint. The author does not test BD Rebuilder with every update of avisynth filters. So the ultimate responsibility of not using the recommended version is with the user.
(I am more sceptical that something got possibly messed up with your K-lite codec pack).

My codec pack is fine, recently updated. If I need to install the much older AviSynth 2.6 or remove all my precious codecs just to satisfy BD Rebuilder and make it work, no way! I would rather use another application, if any, or recompress the video from the original file and re-author the AVCHD folder with MultiAVCHD. Besides, I don't think using software encoders in BD Rebuilder would be much faster than using x264 or x264vfw codec in VirtualDub to recompress the video from the original file. So it's not worth it. I will try it once in a while with NVEnc encoder. If I am lucky enough that the target folder is close to 4480MB, OK, otherwise plan B: recompress the video with VirtualDub.

PS: In case you are wondering, the same inaccuracy issue is in all applications using hardware encoders. This includes Fastflix with NVEncC or FFMPEG with NVEnc acceleration, Handbrake with Nvidia AVC or Nvidia HEVC and Avidemux with Nvidia AVC/HEVC. I calculate the bitrate with AVCHD Calculator and I put it in the application settings. If I get close to the target size, hurray! Pour the champagne! If I get smaller or larger file I cannot fix it by using a little higher or a little lower bitrate. For small differences I get exactly the same file size, this is very annoying. For larger bitrate differences I go way off target. The only workaround is to use VirtualDub to encode in software. In the meantime I have lost too much time trying to guess the correct bitrate for hardware encoding that I could have used VirtualDub in the first place. So I believe hardware encoders are best if you don't care about the exact file size (such as when preparing a master video file for conversion to another format later) or you want constant quality. If you need specific target size, don't waste your time, use a software encoder in the first place which is far more accurate.