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December 5

Model no: PA5024U-1BRS, Li-on 10.8v, 5200mAh

I possess “Toshiba Satellite L850-166” Laptop, what is the highest “mAh” battery available on this Laptop/Battery model number? 103.230.107.17 (talk) 19:17, 1 December 2016 (UTC)[reply]

You can generally find replacement batteries by searching for the laptop or battery model. In this case, this is the first Google search result for that battery model. clpo13_(talk) 19:25, 1 December 2016 (UTC)[reply]

Yes I've noticed, reason for re-asking is, 1) first time, I did not receive the answer requested though was assisted to a better solution which is in the subsection now below as a query, thereafter my research. 2) Due to curiosity as I'm unable to grasp this second time. 103.230.105.10 (talk) 19:35, 1 December 2016 (UTC)[reply]

External Battery

I possess “Toshiba Satellite L850-166” Laptop, I require a battery that will replace the following: Model no: PA5024U-1BRS, Li-on 10.8v, 5200mAh.

Requirement:

1) Li-on battery that can be monitored from the monitor screen (just like I currently do now for the existing one using a software), and, as well as from the external battery section.

2) Capability of charging while using and not using the Laptop, while keep the external charging pin inside the Laptop...

3) A Li-on battery i.e. quick to charge e.g., like the "Mission e- Porche"...

103.230.107.17 (talk) 19:17, 1 December 2016 (UTC)[reply]

Purely for curiosity, 103.230.107.17 (so you do not have to answer), why didn't you post this query on the 'Computers and IT' Reference Desk, where regular responders are more likely to know about this sort of thing than those on the 'Miscellaneous' Desk? {The poster formerly known as 87.81.230.195} 176.248.159.54 (talk) 22:36, 1 December 2016 (UTC)[reply]

Converter

Which one of this file formats (M4A, WMA, AAC, and AAC+) hold the minimalist mb after conversion. And, what easy opensource software is out there that I could do this task.

Note: Graeme Bartlett stated ffmpeg, its command line, I haven't downloaded it yet cause I'm not a programming type guy... Is there anything else?

103.230.106.5 (talk) 19:02, 5 December 2016 (UTC)[reply]

Avanti [1] is a GUI for FFmpeg, it should be easier to get started with. Most of those codecs can shrink so small that the audio/video quality is horrible. You probably don't want the codec that can make the smallest file, because that will sound terrible. Rather, you probably want a codec that can make a small file and still look and sound good to you. We have articles on Codec_listening_test, Comparison_of_audio_coding_formats. SemanticMantis (talk) 20:55, 5 December 2016 (UTC)[reply]

M4A is a container format that can hold AAC, MP3, AC-3, and various other audio formats.

Rather than audio formats, you should think more about encoders, as there is a huge difference in the output quality of different encoders even in the same format at the same bitrate. In particular, the free AAC encoder FAAC has a poor reputation for quality (although that was years ago and it's possible that it's improved).

This page ranks ffmpeg's encoders from best to worst (for quality at a given size) as libopus > libvorbis ≥ Fraunhofer FDK AAC > aac (FAAC?) > (others you don't care about). Use libopus if you can, but you probably can't, because support for the Opus format is poor. I use libvorbis, as all the devices that I care about support the Ogg Vorbis format, but I think support is worse than AAC. You may be best off with FDK AAC in AAC+ (HE-AAC) mode. I'd advise against using any other AAC encoder. WMA isn't on that list, unfortunately. I think it's comparable to AAC (if you use Microsoft's encoder).

For Windows, foobar2000 is a good friendly GUI transcoding program, but it's not open source (it is free of charge). -- BenRG (talk) 00:45, 6 December 2016 (UTC)[reply]

I'd be wary of trusting the ffmpeg wiki info. I don't see how the quality comparisons were determined. Most listening tests I've seen generally find the best AAC codes perform better than the best Vorbis codecs at a number of bitrates e.g. [2] although I'm not sure whether the difference is that stark that you're likely to notice if you aren't doing an ABX, ABC or similar or experience at listening to compression artifacts and your personal preference may vary anyway, e.g. see [3] and [4]. Especially at high bitrates (say 128kbps or higher).

ffmpeg is probably right about Opus however. I'm also not sure if FDK is the best AAC encoder although the others may not be open source or part of ffmpeg so FDK may be the best open source one, I'm not sure about that. (I think Apple/Quicktime's AAC is often found to be best. Nero also sometimes gets good results but seems a bit more uncertain sometimes even losing to AoTuV's Vorbis.) Likewise if you did want to use vorbis, my impression is most people who test find AoTuV is better than libvorbis or they can't notice the difference.

I think one thing is that by now, most most codecs are advanced enough and most people have enough space that they're using high enough bitrates that it doesn't rarely matter for most so decent listening tests based on recent codecs are rare. (You'll still find some small personal ones, but multiusers ones not so much.)

I mean heck, many people probably can't even tell the difference between 128kbps MP3 and lossless for many samples. See [5] and [6] and and for some additional discussion and links. [https://hydrogenaud.io/index.php/topic,106713.0.html has some preferences but generally without evidence.

If you are really interested, the links and info there will probably help you to design your own listening tests. Ultimately it's a moot point if someone can tell the difference between AoTuV and Apple AAC and lossless at 128kbps if you can't. (Presuming these are only intended for you.) Note thought, you shouldn't assume if you have poor equipment you won't notice the difference, see e.g. [7].

You may also want to consider what you actually want and need. HE-AAC is better if you really want a really low bitrate. But at something like 96kbps you probably don't want HE-AAC. And at 96kbps you can store over 90 hours in 4GiB or GB. Do you really need it smaller than that?

Nil Einne (talk) 03:10, 6 December 2016 (UTC)[reply]

P.S. WMA 10 Pro doesn't seem to get much love in recent listening tests or in general. I don't think it's necessarily a bad codec, but it lacks the patent unencumbered advantage of Vorbis and due to it being new and Microsoft (rather than AAC MPEG) never really gained the widespread compatibility of AAC surely not helped by Microsoft's failure to gain much of a foot hold in a mobile device market and their updates to the format and DRM issues [8]. (Although because of their efforts and other things, it was and is sometimes supported in addition to MP3 where other codecs aren't e.g. [9].) And it's not clearly superior to AAC/Vorbis (well someone in the first link suggests WMA10 Pro may be but I'm not sure if this may just be because it supports high frequences etc which aren't actually needed anyway).

I wonder whether a lack of codec development by Microsoft may have meant it now clearly loses compared to the best AAC or Vorbis (i.e. although the codec design may be no worse, software by now clearly is) but I'm seeing some results e.g. [10] which suggest perhaps it's not too bad. Also perhaps [11].

However I suspect that in most cases if WMA compatibility isn't an issue for you, this probably suggests you're using devices where you can install your own codecs, so Opus is likely the better bet. So it's probably a rare case that WMA is the best choice. The exception would be I guess if you're locked into Microsoft ecosystem and can't be bothered installing your own codecs (or can't in some cases, e.g. certain portable audio players and car or home audio systems).

Nil Einne (talk) 04:07, 6 December 2016 (UTC)[reply]

SemanticMantis, BenRG, Nil Einne, Graeme Bartlett:

This is my mobile phone. I'm currently unable to watch downloaded videos files (guessing due to the evolution of file formats). Which converter should I use in order to watch clips, on the phone hastle free. ffmpeg flopped out. The GUI doesn't open for some reason. 103.230.105.18 (talk) 20:00, 7 December 2016 (UTC)[reply]

I'm sorry, I cannot help with that. If you don't get a satisfactory answer here, you may try posting that info and asking at a dedicated cell phone help desk, for example Reddit's /r/cellphones. Good luck! SemanticMantis (talk) 20:05, 7 December 2016 (UTC)[reply]