The drawback is that 4xm encoding takes forever and the file size of a .4xm after converting is large.
But, it is an interesting format.
https://wiki.multimedia.cx/index.php/4xm_Format
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Selfboot Script v4:
If any1 wants to test the 4xm player that is included on one of the DreamOn disks..
I made a quick batch script to create a selfboot .cdi
https://www.dreamcast-talk.com/forum/vi ... 25#p167005
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4XM Video Player:
----Ian Micheal wrote:Sm player plays 4xm files dreamcast encoded with sound and shows file info it's a start traced this from 2003 post about ffmpeg
https://www.smplayer.info/
4XM Tools/Docs Etc:
4XM Encoder/Compression & More:
check MoeFoh's attachment below.. (ian_4xm[tools]Movie.rar)
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4XM details for playing video on dreamcast:
Here is the mediainfo details of matrix4xm.mp4 (decoded from source matrix.4xm)
Overall bit rate: 1052
Video: 916kbps, 640x368 (1.739), at 25.000 fps, AVC (High 4:4:4 Predictive@L3)(CABAC/4 Ref Frames)
Audio: 128kbps, 44.1Khz, 2 channels, AAC(LC)
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4xm codec:
https://www.ffmpeg.org/~michael/4xm.html
https://github.com/intel/ffmpeg_libyami ... odec/4xm.c
https://gfiber.googlesource.com/vendor/ ... rmat/4xm.c
https://code.soundsoftware.ac.uk/projec ... xm_8c.html
https://stuff.mit.edu/afs/sipb/project/ ... odec/4xm.c
https://stuff.mit.edu/afs/sipb/project/ ... codec/sh4/
list of games that use 4xm format:
https://www.mobygames.com/game-group/mi ... e-4x-movie
4xm samples:
https://samples.mplayerhq.hu/game-formats/4xm/
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----Ian Micheal wrote:Ok we can use ffmpeg to decode 4xm files like matrix or others withthis will help to see what the real stats are to help with encodingCode: Select all
ffmpeg -i Ducati.4xm intro.mp4
Code: Select all
Guessed Channel Layout for Input Stream #0.1 : stereo Input #0, 4xm, from 'VIDEO.4XM': Duration: 00:08:10.64, start: 0.000000, bitrate: 1411 kb/s Stream #0:0: Video: 4xm, rgb565le, 640x368, 25 tbr, 25 tbn, 25 tbc Stream #0:1: Audio: adpcm_4xm, 44100 Hz, stereo, s16p, 1411 kb/s Stream mapping: Stream #0:0 -> #0:0 (4xm (native) -> mpeg1video (native)) Stream #0:1 -> #0:1 (adpcm_4xm (native) -> mp2 (native))
Ian Micheal wrote:Data Rate Defines the throughput in bytes per second. The default value for
this parameter is 800 000 i.e. 780 Kb per second corresponding
to a CDX8 drive. You should count about 100 Kb per second for
a single-speed drive. This calculation takes into account both
images and sound. If there is no sound it is for the images alone.
So that's what the data rate is maybe for gdemu we could up this for tests