is it real hows it done??????
175 hours on 1 DISC ? :shock:
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hitenmdesai
- Joined: Sat Apr 21, 2007 3:58 am
175 hours on 1 DISC ? :shock:
is it possible ? ive seen a VCD with that much of data. the owner claimed... didnt actually see all of it but the video was of VCD quality
is it real hows it done??????
is it real hows it done??????
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Purge
- Joined: Mon Oct 10, 2005 9:18 am
- Location: Under Aus
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Willen
- Now in Hi-Def!
- Joined: Sun Jul 10, 2005 1:50 am
- Status: Melancholy
- Location: SOS-Dan HQ
Not possible. Let's understand why.
VCD (VideoCD)
Based on existing audio CD (Compact Disc) and CD-ROM physical media, it uses MPEG-1 video compression and MPEG-1 Audio Layer II (MP2) audio compression.
Video is encoded at 352x240 resolution, 29.97 fps (NTSC video) or 23.976 fps (NTSC film), or at 352x288 resolution, 25 fps (PAL video), constant bit rate (CBR), 1,150 kbps or less (to maintain compatibility with 1x CD drives). Audio is set at 224 kbps, CBR, at 44.1 kHz sampling rate, with 1 stereo or 2 mono channels.
Typical play (recording) time of a VCD is 74 minutes for a 650MB CD, 80 minutes for a 700MB CD. Notice that the play times are the same as an audio CD due to the use of similar data rates/transfer speeds.
A VideoCD IS NOT the same as a CD-ROM/CD-R with video files recorded on it as data. If the disc is not playable in a standard, stand-alone VCD or DVD player, then it isn't a VCD. Some stand-alone VCD and DVD players can play back video files on a CD-ROM/CD-R (e.g. 'MPEG-4'/DivX-compatible units), which causes confusion about the type of disc that is being played.
There are some non-standard types of VCDs (DVCD, KVCD) that can be created with longer playing times of up to 120 minutes, but many stand-alone players may have a harder time reading these discs.
It is possible that the disc is actually a...
CVD (China Video Disc)
Very similar to VCDs and originally designed for the Chinese market as a successor to the VideoCD, it eventually was folded into the SVCD (Super Video CD) format. Video specs are MPEG-2 encoding at 352x480, 29.97 or 23.976 fps for NTSC and 352x576, 25 fps for PAL, up to 2,600 kbps at constant or variable bit rate (VBR). Audio is MPEG-1 Audio Layer II at 44.1 kHz like VCD, but can be recorded with joint stereo, stereo or dual channel audio streams at 128, 192, 224 or 384 kbps, mono audio streams at 64, 96 or 192 kbps.
It does not have a specified GOP (group of pictures) limit for encoding so it is possible to have a fairly highly compressed video file IF there is very little change between frames. Typical MPEG-2 encoders for SVCD and DVDs use a GOP of 15 for PAL and 18 for NTSC frame-based material (double for field-based material). After a certain GOP length, you reach a point of diminishing returns. It will be harder for players to recover from errors (glitches will stay on the screen longer) and other issues.
But even with these 'tweaks', a CVD will not achieve a 175 hour capacity. It becomes more plausible if the disc is a...
DVD (Digital Versatile Disc)
Uses a disc similar in physical size to a CD, and at first glance can easily be mistaken for one, but has the capacity to hold up to 17.1GB of data on a dual-layer double-sided disc. The more common recordable dual-layer single-sided versions hold up to 8.5GB of data. I've never seen a recordable 17.1GB DL/DS disc, although it is possible for a manufacturer to produce one. A single-layer, single-sided DVD will hold 4.7GB (4.3GiB), or the equivalent of about 7 CDs.
MPEG-2 is used for encoding video and audio can be recorded as uncompressed Linear PCM, MPEG-1 Audio Layer II (MP2), Dolby Digital (AC3), or DTS. Normal video resolutions are 720x480, 29.97 fps for NTSC and 720x576, 25 fps for PAL, 16:9 or 4:3 aspect ratio, up to 9,800 kbps. Additional available NTSC video resolutions are 704x480, 352x480, and 352x240. PAL resolutions also include 704x576, 352x576, and 352x288. Optionally, you can use MPEG-1 for video (up to 1,856 kbps) using the same VCD standards (see above). Audio is 48 or 96 kHz (PCM, DTS), 16 or 24 bits for PCM, and can contain up to 7.1-channels. Multiple audio tracks are possible.
Even then, without going out of the DVD specs too wildly, you can safely record about 10 hours (at EP) of video on a double-layer DVD and have it play on a stand-alone player. This is compared to the normal 3.5 hour capacity (at SP) of a 8.5GB disc. Longer times are possible with certain source materials and encoder settings without major playback issues. Of course, at these long playback times, the video (and audio) quality must be compromised to reach these capacities. This means lower quality (resolutions and bit rates). Single-layer 4.7GB DVDs will obviously hold less - 6 hours (at EP) is the typical maximum.
Now, if the DVD is used to store video files (AVI, DIVX, MKV, MP4, MPG, WMV, etc.), then if the resolutions and bit rates are low enough, it may be possible to cram 175 hours of video on a single disc (especially if it is a double-layer DVD). But the video quality would probably be lower than the typical VCD and definitely lower than that of a SVCD or DVD. I'm not willing to encode 175 hours of low resolution, low bit rate video to find out if the claims of VCD quality are true.
If you really need to know how is it done, then ask the owner of the 'VCD'. Either he will know or the person who made it for him.
The real question you should be asking is, "why would anyone want to put 175 hours on one disc?"
VCD (VideoCD)
Based on existing audio CD (Compact Disc) and CD-ROM physical media, it uses MPEG-1 video compression and MPEG-1 Audio Layer II (MP2) audio compression.
Video is encoded at 352x240 resolution, 29.97 fps (NTSC video) or 23.976 fps (NTSC film), or at 352x288 resolution, 25 fps (PAL video), constant bit rate (CBR), 1,150 kbps or less (to maintain compatibility with 1x CD drives). Audio is set at 224 kbps, CBR, at 44.1 kHz sampling rate, with 1 stereo or 2 mono channels.
Typical play (recording) time of a VCD is 74 minutes for a 650MB CD, 80 minutes for a 700MB CD. Notice that the play times are the same as an audio CD due to the use of similar data rates/transfer speeds.
A VideoCD IS NOT the same as a CD-ROM/CD-R with video files recorded on it as data. If the disc is not playable in a standard, stand-alone VCD or DVD player, then it isn't a VCD. Some stand-alone VCD and DVD players can play back video files on a CD-ROM/CD-R (e.g. 'MPEG-4'/DivX-compatible units), which causes confusion about the type of disc that is being played.
There are some non-standard types of VCDs (DVCD, KVCD) that can be created with longer playing times of up to 120 minutes, but many stand-alone players may have a harder time reading these discs.
It is possible that the disc is actually a...
CVD (China Video Disc)
Very similar to VCDs and originally designed for the Chinese market as a successor to the VideoCD, it eventually was folded into the SVCD (Super Video CD) format. Video specs are MPEG-2 encoding at 352x480, 29.97 or 23.976 fps for NTSC and 352x576, 25 fps for PAL, up to 2,600 kbps at constant or variable bit rate (VBR). Audio is MPEG-1 Audio Layer II at 44.1 kHz like VCD, but can be recorded with joint stereo, stereo or dual channel audio streams at 128, 192, 224 or 384 kbps, mono audio streams at 64, 96 or 192 kbps.
It does not have a specified GOP (group of pictures) limit for encoding so it is possible to have a fairly highly compressed video file IF there is very little change between frames. Typical MPEG-2 encoders for SVCD and DVDs use a GOP of 15 for PAL and 18 for NTSC frame-based material (double for field-based material). After a certain GOP length, you reach a point of diminishing returns. It will be harder for players to recover from errors (glitches will stay on the screen longer) and other issues.
But even with these 'tweaks', a CVD will not achieve a 175 hour capacity. It becomes more plausible if the disc is a...
DVD (Digital Versatile Disc)
Uses a disc similar in physical size to a CD, and at first glance can easily be mistaken for one, but has the capacity to hold up to 17.1GB of data on a dual-layer double-sided disc. The more common recordable dual-layer single-sided versions hold up to 8.5GB of data. I've never seen a recordable 17.1GB DL/DS disc, although it is possible for a manufacturer to produce one. A single-layer, single-sided DVD will hold 4.7GB (4.3GiB), or the equivalent of about 7 CDs.
MPEG-2 is used for encoding video and audio can be recorded as uncompressed Linear PCM, MPEG-1 Audio Layer II (MP2), Dolby Digital (AC3), or DTS. Normal video resolutions are 720x480, 29.97 fps for NTSC and 720x576, 25 fps for PAL, 16:9 or 4:3 aspect ratio, up to 9,800 kbps. Additional available NTSC video resolutions are 704x480, 352x480, and 352x240. PAL resolutions also include 704x576, 352x576, and 352x288. Optionally, you can use MPEG-1 for video (up to 1,856 kbps) using the same VCD standards (see above). Audio is 48 or 96 kHz (PCM, DTS), 16 or 24 bits for PCM, and can contain up to 7.1-channels. Multiple audio tracks are possible.
Even then, without going out of the DVD specs too wildly, you can safely record about 10 hours (at EP) of video on a double-layer DVD and have it play on a stand-alone player. This is compared to the normal 3.5 hour capacity (at SP) of a 8.5GB disc. Longer times are possible with certain source materials and encoder settings without major playback issues. Of course, at these long playback times, the video (and audio) quality must be compromised to reach these capacities. This means lower quality (resolutions and bit rates). Single-layer 4.7GB DVDs will obviously hold less - 6 hours (at EP) is the typical maximum.
Now, if the DVD is used to store video files (AVI, DIVX, MKV, MP4, MPG, WMV, etc.), then if the resolutions and bit rates are low enough, it may be possible to cram 175 hours of video on a single disc (especially if it is a double-layer DVD). But the video quality would probably be lower than the typical VCD and definitely lower than that of a SVCD or DVD. I'm not willing to encode 175 hours of low resolution, low bit rate video to find out if the claims of VCD quality are true.
If you really need to know how is it done, then ask the owner of the 'VCD'. Either he will know or the person who made it for him.
The real question you should be asking is, "why would anyone want to put 175 hours on one disc?"
Having trouble playing back videos? I recommend: 
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hitenmdesai
- Joined: Sat Apr 21, 2007 3:58 am
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AMV_4000
- Joined: Wed Apr 10, 2002 6:29 am
- Location: USA
- Contact:
175 hours or minutes??Willen wrote: DVD (Digital Versatile Disc)
Uses a disc similar in physical size to a CD, and at first glance can easily be mistaken for one, but has the capacity to hold up to 17.1GB of data on a dual-layer double-sided disc. The more common recordable dual-layer single-sided versions hold up to 8.5GB of data. I've never seen a recordable 17.1GB DL/DS disc, although it is possible for a manufacturer to produce one. A single-layer, single-sided DVD will hold 4.7GB (4.3GiB), or the equivalent of about 7 CDs.
MPEG-2 is used for encoding video and audio can be recorded as uncompressed Linear PCM, MPEG-1 Audio Layer II (MP2), Dolby Digital (AC3), or DTS. Normal video resolutions are 720x480, 29.97 fps for NTSC and 720x576, 25 fps for PAL, 16:9 or 4:3 aspect ratio, up to 9,800 kbps. Additional available NTSC video resolutions are 704x480, 352x480, and 352x240. PAL resolutions also include 704x576, 352x576, and 352x288. Optionally, you can use MPEG-1 for video (up to 1,856 kbps) using the same VCD standards (see above). Audio is 48 or 96 kHz (PCM, DTS), 16 or 24 bits for PCM, and can contain up to 7.1-channels. Multiple audio tracks are possible.
Even then, without going out of the DVD specs too wildly, you can safely record about 10 hours (at EP) of video on a double-layer DVD and have it play on a stand-alone player. This is compared to the normal 3.5 hour capacity (at SP) of a 8.5GB disc. Longer times are possible with certain source materials and encoder settings without major playback issues. Of course, at these long playback times, the video (and audio) quality must be compromised to reach these capacities. This means lower quality (resolutions and bit rates). Single-layer 4.7GB DVDs will obviously hold less - 6 hours (at EP) is the typical maximum.
Now, if the DVD is used to store video files (AVI, DIVX, MKV, MP4, MPG, WMV, etc.), then if the resolutions and bit rates are low enough, it may be possible to cram 175 hours of video on a single disc (especially if it is a double-layer DVD). But the video quality would probably be lower than the typical VCD and definitely lower than that of a SVCD or DVD. I'm not willing to encode 175 hours of low resolution, low bit rate video to find out if the claims of VCD quality are true.
If you really need to know how is it done, then ask the owner of the 'VCD'. Either he will know or the person who made it for him.
The real question you should be asking is, "why would anyone want to put 175 hours on one disc?"
i know i can pack a TON of hours on a DVD at 352x240 at lot bitrate...
and 175 minutes on a VCD may be what they are talking about
but i do agree that 175 hours is quite impossible without dual or quad layers or hd/bluray discs...