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Better or worse error correction in the mp3 codec ?
I'd rather be phishing!
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It's almost certainly NOT the MP3 itself. I would suspect the player. Try another one.
- I would love to change the world, but they won’t give me the source code.
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See my other responses. I've tried multiple players, and - in some cases, if I have an older backup that plays fine - a binary comparison will show the files are different...
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As others have said, I would suspect the player not the files. The only 'scratches' I hear from my library are those tracks that were ripped from CDs.
BTW, long ago I started a personal project to catalog my music library by using the ID3 tags. I found out quick that they are totally unreliable and have major shortcomings that made them unsuitable for that purpose. (truncated names either at 30 or 60 chars depending on version)
"Go forth into the source" - Neal Morse
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kmoorevs wrote: (truncated names either at 30 or 60 chars depending on version) Those are ID3v1 tags. ID3v2.4, which has been the dominant specification for almost 15 years, is a lot more flexible. I use a program called MP3tag[^] and have found it to work well.
Software Zen: delete this;
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That's the one I use.
I find it doubtful it's the player, as I've tried WMP, VLC (my player of choice) and foobar2000.
Also--and more importantly--every once in a while I come across one of those files, then look it up in my most recent backup set. If I'm lucky, I didn't yet overwrite the "good" backup of the MP3 with the version on my NAS (now with the audible clicks). And if I do a file compare, the files are different. I think that, by itself, rules out any sort of playback mechanism subtleties between different players.
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And now over to the next step: corrupting MP4's
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This sort of thing is part of the reason I don't convert my DVD rips (AUDIO_TS/VIDEO_TS, VOBs and all) into single-file formats...
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Wise, very wise
TS stands for Transport Stream btw. a format that I don't encounter very often in my line of work.
I once had to analyze a TS, it was hard to find any information about that !
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I've come across .TS files before, and I believe they tend to originate from Tivo and live stream type of boxes that receive streaming data you're not "supposed" to get to. And it's hardly compressed (to the point of being total overkill - as in, gigabytes for just a few minutes worth of video).
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My first encounter with .TS was with an early version of a Chinese Digital Video Recorder.
They tried to sell it as "able to deliver H264 streams", but the streams were not in standard H264 format at all, instead it produced .TS
They cleaned up their act btw (but you never know what tricks they are up to next of course)
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As I've been made to understand, don't confuse codec with container.
I'm just glad I don't write software that tries to do anything with video files.
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.TS transport stream video is the format used by my digital TV in the UK when it records DVB programmes in SD to USB thumb drive in real time, I also have a Grundig box that does the same thing.
I am guessing that this is the video format inside the DVB digital video broadcast signal.
No problem playing this back on TV,Mac or PC using VLC. Sometimes have to rename as .MPG to play.
Single container files approx 2Gb per hour = 25kbps audio and 15Mbps video at 25fps in SD format.
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Member 12364390 wrote: Single container files approx 2Gb per hour = 25kbps audio and 15Mbps video at 25fps in SD format.
That sounds a lot more reasonable than those I've come across. I mean, I have standard 3-4 minute music videos (that only last as long as a song) roughly 1.2GB.
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What I've sometimes experienced is that I have an MP3 in 128 or 192 bits, but some player is like "let's make that 320!" and that's simply not possible and it results in clicks and ticks.
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If it was hearing loss, I wouldn't be hearing the glitches that weren't there previously.
But I needed the laugh.
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I have had similar experiences in two areas: First, when I come across a CD issue of some vinyl record I used to love years ago, but haven't played for a long time. I rush home, put the CD in the player, and am disappointed: It doesn't sound nearly as good as I remember the old vinyl! Far less punch, duller in the higher frequencies,...
So I dig up the old vinyl record for a direct comparison (I haven't updated my stereo for many years; the setup is the same as in the old days, and I have kept all the old vinyls). Without exception, the CD quality is significantly better in a side-by-side comparison. Through the rosy haze of memory, the sound quality of vinyl recordings had improved to beyond the perfect reproduction...
Second: I had all my Super-8 movies digitized. Setting up the projector, shading the windows, mounting the screen... We never did that anymore, too much hassle. The digitizing shop did a poor job: Images were grainy, movements jerky, color was poor. Again, I set up the analog equipment for the same image size as my video screen, and compared side by side. Especially the movements were far more jerky in the original. They appearently did som sort of morphing when converting the 18 fps Super-8 into 25 fps video - interpolating movements between the frames. Yet they managed to retain a sharpness where I can see the indiviual grains in the photograhic film, when I stop the video at a single frame.
So: Maybe the sound of your MP3s never were better. They always had the click and ticks and garbled sound - but that was the norm in those days. (When CDs arrived, you could buy T-shirts that said "Music will never be the same without the hizz, clicks and pops".)
You may know that Norway was the first - and I belive still the only - country to close down the national FM radio networks during 2017; only a few community radios are left on FM. A fairly large number of "rebels" were fiercely fighting against digital radio, and painted the most rosy images of how perfect FM is, both in coverage, sound quality, channel selection etc. I saw what was coming, so before the FN teardown started, in 2016 and 2017, I spent my summer vacations driving around the country with a brand new high end FM/DAB car radio, recording (on a digital recorder, using the line out from the car radio) the sound while switching back and forth between the DAB and the FM transmission of the same channel, and I took notes of available channels as I moved around.
I was not surprised: Once FM was gone, I was blamed for lying. For corrupting the recordings of the FM sound just to make it sound worse. For using some cheap, poor quality and low sensitivity receiver when I reported 'no FM coverage'. Now that we no longer can drive the same routes for the FM zealots to try to pick up some FM signal, they can claim that it was there - I am the one lying, claiming it wasn't!
The recordings of the FM/DAB comparison remains in my archives. I can play them to anyone who insists that FM had perfect quality. They may accuse me of lying. But I know that nothing is better than nostalgia at raising the quality level of something you once had.
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Interesting theory, but it's nowhere near that subtle. You'd have to be pretty much deaf to not hear one of those loud CLICKs.
I should find some app that displays the sound wave. I'm sure those clicking noises would stand out visually as well.
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Isn't that available in practically speakin any sound editor? (My choice is Steinberg WaveLab, but there are free alternatives available.)
In any case: MP3 encoding can be compared to text encryption (that is, modern methods - not the rot13 class!): No bit error could change the wording of your encrypted letter to, say, add a "not" before a claim, and the encrypted text still being valid. The only way to do that is to decrypt, edit and re-encrypt. Similar with MP3: No bit error could add a click to the MP3 encoded sound, leaving a valid MP3 encoded file, without decoding it first and re-encoding it afterwards.
I can assure you: Those clicks were not added to the file while it was MP3 encoded! Any click sound was either present in the original sound before MP3 encoding, or they are added in the decoding/playback process. Any bit rot that could have affected the sound would have left the file as garbage, invalid MP3 encoding that couldn't be decoded at all. (The MP3 format provides some error correction to handle bit errors, but this corrects the error, and doesn't leave a click.)
Of course: In theory, a really huge amount of bit errors might change your file into a bit pattern that happens to be another valid MP3 file. In theory, bit errors might also change your MP3 file into a triple-X rated JPEG image. That doesn't happen.
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Member 7989122 wrote: Isn't that available in practically speakin any sound editor? (My choice is Steinberg WaveLab, but there are free alternatives available.)
Possibly. I just don't have any, as I generally have absolutely no need for them.
Member 7989122 wrote: No bit error could add a click to the MP3 encoded sound, leaving a valid MP3 encoded file, without decoding it first and re-encoding it afterwards
I'm not buying that. In fact, right now, I just copied an MP3 file to a temp folder, loaded Visual Studio, loaded the MP3 with it and, using its binary editor, changed exactly 3 bytes; one near the start, another near the middle, and the third near the end, and saved everything back. No encoding involved in doing that, I'm sure you'll agree? VLC didn't complain the file was suddenly invalid, and playing it back, a 3-byte difference is probably so small I couldn't hear anything wrong from start to finish (after all, when audio is sampled 48,000 times a second, a 3-byte change is assuredly not enough for anyone to hear it).
So I then selected a large random block of binary data with VS, hit Delete, and saved it again. This time, I definitely heard a glitch, in the sense that it clearly skipped over a fraction of a second at the spot I deleted data from the file.
If what you're saying were true, how would streaming possibly have any sort of fault tolerance?
Member 7989122 wrote: I can assure you: Those clicks were not added to the file while it was MP3 encoded!
?? I never made any such claim, and I'm certainly not even thinking this is what happened. What I've kept saying all along is that I had files sitting on disk, that I know had played back just fine in the past, then one day, all players play back some audible glitches for a small subset of files, that could best be described as a tick or click noise, but carry on playing as it if was supposed to be part of the recording. In other words, the binary data has changed (and I had WinMerge confirm that's the case--comparing with an older backup that worked fine). In some cases, even the byte count remained exactly the same.
Member 7989122 wrote: Of course: In theory, a really huge amount of bit errors might change your file into a bit pattern that happens to be another valid MP3 file. In theory, bit errors might also change your MP3 file into a triple-X rated JPEG image. That doesn't happen.
That much we agree on.
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Maybe your hearing is improving.
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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That happened to me quite several times, exactly as you say, but not during the last years. I don't understand in some of the replies if people mean "the player broke it" or "the specific player plays the noise". Anyway I could hear the errors no matter the player. I finally assumed that it was hardware, a disk corruption. But I don't agree with the "why would this only happen with MP3 files?", because that has happened to me with any kind of file, like images or other immutable documents.
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If the filesize is different then something wrote data to alter the file, either accidentally or on purpose. So you know what happened, you just don't know what did it. Is there any rhyme or reason to which songs have been affected- a certain label or artist or genre? Do you know, even roughly, the date when you first created the mp3 and what date is listed as the last modified date now? If you do a search on copyright or music using a range around that time period, perhaps in conjunction with the label or artists there may be some online talk about music files being altered around that time period.
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Good idea. It never occurred to me to check those thinks. Next time I'll take a look at it comparing the file details with their copies in the backup. Anyway I cannot remember to have found that issue in the last years, so I just assumed that whatever was causing it, just got improved.
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