[FFmpeg-user] ffmpeg output list question
Mark Filipak
markfilipak.windows+ffmpeg at gmail.com
Mon Dec 16 10:03:14 EET 2019
On 12/15/2019 06:58 PM, Carl Eugen Hoyos wrote:
> Am So., 15. Dez. 2019 um 22:20 Uhr schrieb Mark Filipak
> <markfilipak.windows+ffmpeg at gmail.com>:
>>
>> On 12/15/2019 02:38 PM, Carl Eugen Hoyos wrote:
>>> Am So., 15. Dez. 2019 um 16:50 Uhr schrieb Mark Filipak
>
>>> FFmpeg (and digital transcoders in general) doesn't know about fields,
>>> it can only work with frames. (This is also related to the specifications
>>> of sane video codecs.)
>>
>> If ffmpeg doesn't know about fields, how can it decode interlaced content?
>
> The mentioned specifications require that conforming decoders output
> frames...
Carl, that's the most important information I've received to date. It
changes most of all my research -- mostly, it simplifies things. Thank
you very, very much.
I knew that ffmpeg encoders output solely frames, but I assumed that,
when an interlaced container was encountered, ffmpeg decoders (hence
HandBrake) worked with fields.
Due to the German in your messages, I assume you're in Europe. My
research needs some PAL VOB samples of the following:
- Vintage "PAL" Cinematic Source -- Purely 24 FPS content (no VBR) in an
25 FPS container (that plays at 25 Hz with 4% speedup).
- "PAL" Cinematic Source -- 25 FPS source (25th frame repeat) in a 25
FPS container (I currently have only 1 modern "PAL" movie sample).
- PAL TV Source -- 25 FPS sequential fields (from PAL TV).
- Mixed PAL Source -- PAL TV show with embedded movie clips (e.g., some
"Making of" documentaries).
- Vintage Mixed PAL Source -- Vintage PAL TV show (4% speedup) with
embedded movie clips (e.g., some "Making of" documentaries).
Do you know how/where I can obtain samples of the 5 source videos above?
=== Details ===
I've found, when VBR sources contain mixed sequential/progressive
content (example: Mixed NTSC TV with embedded 24 FPS clips), that line
doubling at 60 FPS (instead of decombing) produces a better transcode. I
assume that the same would be true for PAL at 50 FPS, but I don't have
any samples to confirm it.
Currently, getting the best HandBrake transcode is a matter of
trial-&-error. I'm trying to use the reports returned by
ffmpeg -ss 30.0 -i %1 -filter:v idet -frames:v 900 -an -f rawvideo -y NUL
to change that.
As I wrote in my initial post, so far I've been wildly successful. My
approach may be unique. It could revolutionize HandBrake -- it could
turn HandBrake into a truly 'one-click' transcoder. But I need some
sample PAL VOBs to proceed.
Best Regards, and Thanks Again! Happy Holidays!
Mark.
More information about the ffmpeg-user
mailing list