FFMPEG & IDM download same file but result in different size?

[pir8skin]

I'm trying to download music videos from vevo.com, I first started to use ffmpeg...until I discovered it was much easier to use Internet Download Manager to grab them. I downloaded the same music video with both programs, but when I compare the file size....they don't match. Can someone explain why this is? Here is the code I used for ffmpeg...

ffmpeg -i "http://hls-lvl3.vevo.com/v3/hls/2014/09/US0459300260/a41a9736-1dfb-475e-b7b7-31087fc44565/5200/us0459300260_5200k_1920x1080_h264_5200_aac_128.m3u8" -c copy us0459300260_5200k_1920x1080_h264_5200_aac_128.m3u8.ts

FFMPEG= 171,244,312 bytes

IDM= 172,667,472 bytes

[Baldrick]

It might just be some different muxing(video and audio multiplexing) and header data.

Compare the video details(running time, bitrate, resolution, etc) instead with for example mediainfo.

[pir8skin]

It might just be some different muxing(video and audio multiplexing) and header data.

Compare the video details(running time, bitrate, resolution, etc) instead with for example mediainfo.

Hi Baldrick,

Thanks for your response. I had a feeling it was something like different muxing because the file size is so close. I went ahead and compared the mediainfo and did however find some concerning differences, i.e. file size, overall bitrate, and service name. Resolution was the same for both.

General
ID                                       : 1 (0x1)
Complete name                            : C:\Users\Pir8skin\Desktop\Copy(FFMPEG).ts
Format                                   : MPEG-TS
File size                                : 163 MiB
Duration                                 : 4mn 0s
Overall bit rate mode                    : Variable
Overall bit rate                         : 5 686 Kbps

Menu
ID                                       : 4096 (0x1000)
Menu ID                                  : 1 (0x1)
Duration                                 : 4mn 0s
List                                     : 256 (0x100) (AVC) / 257 (0x101) (AAC)
Service name                             : Service01
Service provider                         : FFmpeg
Service type                             : digital television

General
ID                                       : 1 (0x1)
Complete name                            : C:\Users\Pir8skin\Desktop\Copy(IDM).ts
Format                                   : MPEG-TS
File size                                : 165 MiB
Duration                                 : 4mn 0s
Overall bit rate mode                    : Variable
Overall bit rate                         : 5 734 Kbps


Menu
ID                                       : 4096 (0x1000)
Menu ID                                  : 1 (0x1)
Duration                                 : 4mn 0s
List                                     : 256 (0x100) (AVC) / 257 (0x101) (AAC)
Service name                             : US0459300260
Service provider                         : FFmpeg
Service type                             : digital television

[poisondeathray]

extract the elementary stream(s) for video & audio, and then compare

[aazerty]

Hi ,

I D M is not free !

Have you tried with youtube-dl ?
Give us a link for try .

Cheers .

[pir8skin]

extract the elementary stream(s) for video & audio, and then compare

I used tsMuxeR to demux the audio and video files from both downloads, compared them, and they came out the exact same file size. I also remuxed the video only to .ts and compared them, and the video bitrate was also identical.

Not sure why mediainfo gives a different video bitrate for the original muxed files, but I am much less concerned now. Thank you.