In my current job I've run into anomalies. I will welcome your comments. ISSUE #2: MP4 edit list. The script below causes FFmpeg to make an MP4 edit list.
Why is that? The following script copies video and stretches and recodes audio. set _NAME_=DAS BOOT [1981][2004] 2of2 set _WORK_=c:\work\ set _JOB_=%_WORK_%%_NAME_% set _GET_=%_JOB_%va.mp4 : Before, for %_JOB_%va.mp4, -show_streams says: : v 0.000000..11088.452375 s. : a 0.000000..11086.517000 s. set _PUT_=%_JOB_%va-output.mp4 : After, for %_JOB_%va-output.mp4, -show_streams says: : v 0.000000..11088.452375 s. : a 0.000000..11087.876000 s. set _COPYv_=-map 0:v:0 -c:v:0 copy set _CODEa_=-map 0:a:0 -c:a:0 ac3 -disposition:a:0 0 c: & cd %_WORK_% start /wait cmd /k ffmpeg ^ -itsscale:a 1.0001230100765516536721219209665 ^ -i "%_GET_%" %_COPYv_% %_CODEa_% "%_PUT_%" I did not expect: That the edit list below would be created [note1]. That running time would change [note2]. Edit list: [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] Unknown dref type 0x206c7275 size 12 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] Processing st: 0, edit list 0 - media time: 2002, duration: 266122872 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] Offset DTS by 2002 to make first pts zero. [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] Setting codecpar->delay to 2 for stream st: 0 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] Unknown dref type 0x206c7275 size 12 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] Processing st: 1, edit list 0 - media time: 324580, duration: 532152816 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 276480 @ 180 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 278016 @ 181 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 279552 @ 182 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 281088 @ 183 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 282624 @ 184 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 284160 @ 185 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 285696 @ 186 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 287232 @ 187 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 288768 @ 188 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 290304 @ 189 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 291840 @ 190 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 293376 @ 191 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 294912 @ 192 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 296448 @ 193 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 297984 @ 194 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 299520 @ 195 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 301056 @ 196 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 302592 @ 197 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 304128 @ 198 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 305664 @ 199 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 307200 @ 200 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 308736 @ 201 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 310272 @ 202 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 311808 @ 203 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 313344 @ 204 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 314880 @ 205 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 316416 @ 206 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 317952 @ 207 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 319488 @ 208 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 321024 @ 209 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] drop a frame at curr_cts: 322560 @ 210 [mov,mp4,m4a,3gp,3g2,mj2 @ 000000000261ee80] skip 484 audio samples from curr_cts: 324096 [note1] Despite recoding audio and thereby obviating an edit list, the edit list above was created and attached to the MP4. [note2] The edit list appears to instruct decoders to drop frames. _______________________________________________ ffmpeg-user mailing list -- [email protected] To unsubscribe send an email to [email protected]
