AC-4 Audio?

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Christian
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Joined: Wed Jan 20, 2021 1:29 pm

Re: AC-4 Audio?

Post by Christian »

ferrellsl wrote: Tue Jan 26, 2021 3:35 pm
Here's a Win64 build with the shared libraries. https://www.dropbox.com/s/bze1a5nrhq63u ... d.zip?dl=1

Here's a list of files in the archive:
avcodec-58.dll
avcodec.dll
avdevice-58.dll
avdevice.dll
avfilter-7.dll
avfilter.dll
avformat-58.dll
avformat.dll
avutil-56.dll
avutil.dll
ffmpeg.exe
ffplay.exe
ffprobe.exe
libbz2-1.dll
libiconv-2.dll
libintl-8.dll
liblzma-5.dll
libstdc++-6.dll
libwinpthread-1.dll
libzstd.dll
SDL2.dll
swresample-3.dll
swresample.dll
swscale-5.dll
swscale.dll
zlib1.dll
Awesome thanks, is it possible that you can also compile the 32bit version?

Christian
Posts: 4
Joined: Wed Jan 20, 2021 1:29 pm

Re: AC-4 Audio?

Post by Christian »

Christian wrote: Fri Jan 29, 2021 3:12 am
ferrellsl wrote: Tue Jan 26, 2021 3:35 pm
Here's a Win64 build with the shared libraries. https://www.dropbox.com/s/bze1a5nrhq63u ... d.zip?dl=1

Here's a list of files in the archive:
avcodec-58.dll
avcodec.dll
avdevice-58.dll
avdevice.dll
avfilter-7.dll
avfilter.dll
avformat-58.dll
avformat.dll
avutil-56.dll
avutil.dll
ffmpeg.exe
ffplay.exe
ffprobe.exe
libbz2-1.dll
libiconv-2.dll
libintl-8.dll
liblzma-5.dll
libstdc++-6.dll
libwinpthread-1.dll
libzstd.dll
SDL2.dll
swresample-3.dll
swresample.dll
swscale-5.dll
swscale.dll
zlib1.dll
Awesome thanks, is it possible that you can also compile the 32bit version?

My configure command looks like this:
./configure --prefix=${WORKSPACE} --extra-cflags="-I$WORKSPACE/include" --extra-ldflags="-L$WORKSPACE/lib" --libdir="@loader_path" --arch=x86 --target-os=mingw32 --cross-prefix=i686-w64-mingw32- --enable-cross-compile --disable-static --enable-shared --disable-debug --disable-doc --disable-gpl

Unluckily ffplay is not build, probably I have to create a windows binary too.

Lost Dog
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Re: AC-4 Audio?

Post by Lost Dog »

ferrellsl wrote: Tue Jan 26, 2021 3:35 pm [

Here's a Win64 build with the shared libraries. https://www.dropbox.com/s/bze1a5nrhq63u ... d.zip?dl=1
Is this with the modified source to have it recognize the AC-4 codec?

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

(;-)
Last edited by ferrellsl on Fri May 07, 2021 4:41 pm, edited 2 times in total.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

Lost Dog wrote: Fri Jan 29, 2021 8:30 am
ferrellsl wrote: Tue Jan 26, 2021 3:35 pm [

Here's a Win64 build with the shared libraries. https://www.dropbox.com/s/bze1a5nrhq63u ... d.zip?dl=1
Is this with the modified source to have it recognize the AC-4 codec?
Yes

Christian
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Joined: Wed Jan 20, 2021 1:29 pm

Re: AC-4 Audio?

Post by Christian »

Yes I saw it, thanks - I just wonder why I am unable to compile it without the requirement for those msys shared libraries. It still complains that I have to have a libgcc_s_sjlj-1.dll. I thought static linking should prevent this.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

(;-)
Last edited by ferrellsl on Fri May 07, 2021 4:41 pm, edited 3 times in total.

Lost Dog
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Re: AC-4 Audio?

Post by Lost Dog »

ferrellsl wrote: Fri Jan 29, 2021 9:08 am
Lost Dog wrote: Fri Jan 29, 2021 8:30 am

Is this with the modified source to have it recognize the AC-4 codec?
Yes
Fantastic! Great job! Do you have a list of the files you edited?

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

(;-)
Last edited by ferrellsl on Fri May 07, 2021 4:42 pm, edited 1 time in total.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

(;-)
Last edited by ferrellsl on Fri May 07, 2021 4:42 pm, edited 1 time in total.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

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Last edited by ferrellsl on Fri May 07, 2021 4:42 pm, edited 3 times in total.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

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Last edited by ferrellsl on Fri May 07, 2021 4:42 pm, edited 1 time in total.

KeeterJ
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Re: AC-4 Audio?

Post by KeeterJ »

I want to thank ferrellsl for building an ffmpeg.exe that supports AC-4. You inspired me this weekend to try it. I grabbed an HDHR .mpg file from a DVR server on a Win10 PC and converted it to a traditional .ts transport stream file using

ffmpeg -i "<my input file>.mpg" -y -map 0:0 -vcodec mpeg2video -map 0:1 -acodec ac3 "<my output file>.ts"

To my amazement it worked the first time. I don't need live viewing and this technique will let me save playable video files. This will work until ATSC 3.x "grows up" and becomes the norm for everything.

Here are a few details if somebody else wants to try it:

I tried playing it on several devices and it worked well (except of course there are no subtitles). The resulting mpeg video stream was just a bit fuzzy but tolerable. I'm not very experienced with ffmpeg's multitude of options but I could probably improve the video quality with some experimenting. The AC-4 to AC-3 conversion was good. I save and watch videos using a variety a players (my favorite is JRiver Media Center) and they all were happy with my ATSC 3.0 conversion. Even my 10-year old Beyond TV played it without complaining. For me this helps since I often travel in an RV that is "off the grid" and don't always have a network connection. I carry a large disk drive filled with recorded TV shows.

ffprobe.exe shows my input file as
Input #0, mpegts, from '<my input file>.mpg':
Duration: 01:00:57.94, start: 69849.064389, bitrate: 3134 kb/s
Program 3
Stream #0:0[0x31]: Video: hevc (Main 10) ([36][0][0][0] / 0x0024), yuv420p10le(tv, bt709), 1920x1080 [SAR 1:1 DAR 16:9], Closed Captions, 59.94 fps, 59.94 tbr, 90k tbn, 59.94 tbc
Stream #0:1[0x32](eng): Audio: ac4 (AC-4 / 0x342D4341), 48000 Hz, 5.1(side), fltp
Stream #0:2[0x39](eng): Audio: ac4 (STPP / 0x50505453), 0 channels, fltp

and my output file as
Input #0, mpegts, from '<my converted file>.ts':
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], Closed Captions, 59.94 fps, 59.94 tbr, 90k tbn, 119.88 tbc
Side data:
cpb: bitrate max/min/avg: 0/0/0 buffer size: 49152 vbv_delay: N/A
Stream #0:1[0x101](eng): Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, 5.1(side), fltp, 448 kb/s

This is important to me since I live in a fringe reception area and my ATSC 1.x PBS and NBC signals are weak. Using my HDHR 4K tuner to record ATSC 3.0 from an alternate RF signal lets me watch programs I can't normally see.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

(;-)
Last edited by ferrellsl on Fri May 07, 2021 4:42 pm, edited 1 time in total.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

(;-)
Last edited by ferrellsl on Fri May 07, 2021 4:43 pm, edited 1 time in total.

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