Below you can find detailed information about the different video formats available, as well as the
advantages and disadvantages of each. This quick reference guide is designed to help you decide which format is
best suited to your new project.
| RECORDING SYSTEMS |
| Digibeta |
Broadcast SDTV (Digital Betacam) |
Sony |
| Medium |
1"/2 tape in cassette |
| Standard |
SDTV (625i/25 and 525i/29.97) |
| Coding |
ITU-R BT.601 |
| Compression ratio |
About 2.5:1 (10-bit), 2:1 (8-bit) |
Intra-frame DCT |
| Sampling |
4:2:2 |
| Data bits |
10 or 8 |
| Audio |
4 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
88Mb/s |
| Description |
Standard SDTV workhorse recording system for many years, now nearing the end of its
life. Compression is light, so compression artefacts are rare (but visible once you know what can cause
them).
Widely accepted as being rugged and near-transparent, so multi-generation tape-to-tape editing is
acceptable. Compression is usually disregarded, or quoted as being 2:1, although it clearly cannot be
so for 10-bit data. |
| |
| DV |
Consumer SDTV (Digital Video) |
| Medium |
1"/4 tape in cassette, tracks are 10μm wide, 19.48mm/sec (0.75"/sec) |
| Standard |
SDTV (625i/25 and 525i/29.97) |
| Coding |
ITU-R BT.601 |
| Compression ratio |
5:1 |
Intra-frame DCT |
| Sampling |
4:2:0 (625i/25), 4:1:1 (525i/29.97) |
| Data bits |
8 |
| Audio |
2 channel LPCM
48kHz clock rate
16-bit |
4 channel LPCM
32kHz
12-bit A law |
| Data rate |
25Mb/s |
| Description |
Originally designed as a consumer format for camcorders. Compression artefacts are
plainly visible on difficult pictures, but consumer cameras rarely produce sufficient energy at high
video frequencies to provoke problems. Camcorders usually have a SDTI interface, designated IEEE1394,
for easy downloading of footage into editing software.
There are 12 sweeps across the tape per frame for 625i/25 containing data for 48 lines, 10 tracks for
525i/29.94.
Sound sampling is not locked to the video scans, so there is no guarantee that footage can be edited
without audio clicks. Sound must always be rendered to avoid problems.
The tape can be run in SP or LP modes. In SP mode, the tape advances in steps of 10μm, thus tracks
abut each other, there is no guard band. In LP mode, the tape is used at about 2/3 the speed of SP,
advancing in steps of about 7μm, so it is then not possible to perform insert editing of either video
or sound, since tracks actually overlap each other on the tape. A tape recorded in LP mode may not be
replayable on another DV player. |
| |
| DVCAM |
Professional/Semi-pro SDTV |
Sony and others |
| Medium |
1"/4 tape in cassette, tracks are 10μm wide, 15μm spaced, 19.48mm/sec (0.75"/sec) |
| Standard |
SDTV (625i/25 and 525i/29.97) |
| Coding |
ITU-R BT.601 |
| Compression ratio |
5:1 |
Intra-frame DCT |
| Sampling |
4:2:0 (625i/25), 4:1:1 (525i/29.97) |
| Data bits |
8 |
| Audio |
2 channel LPCM
48kHz clock rate
16-bit |
4 channel LPCM
32kHz
12-bit A law |
| Data rate |
25Mb/s |
| Description |
A development of the original DV format. The tape is used 50% faster than SP DV, by
advancing the tape 15 μm per track. Compression artefacts are plainly visible on difficult pictures,
but the better semi-professional cameras have optical filters to remove the high video frequencies that
would otherwise cause problems. There are 12 sweeps across the tape per frame for 625i/25 containing
data for 48 lines, 10 tracks for 525i/59.94.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software.
Sound sampling is locked to the video scans, so there is a guaranteed, integer, number of sound
samples per frame. |
| |
| DVCPRO25 |
Professional/Semi-pro SDTV (D7) |
Panasonic |
| Medium |
1"/4 tape in cassette, tracks are 18μm wide, 33.8mm/s (1 1/3" per second) |
| Standard |
SDTV (625i/25 and 525i/29.97) |
| Coding |
ITU-R BT.601 |
| Compression ratio |
5:1 |
Intra-frame DCT |
| Sampling |
4:1:1 |
| Data bits |
8 |
| Audio |
4 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
25Mb/s |
| Description |
A development of the original DV format. The tape is used 50% faster than DVCAM, by
advancing the tape 18μm per track. Compression artefacts are plainly visible on difficult pictures,
but the better semi-professional cameras have optical filters to remove the high video frequencies that
would otherwise cause problems.
There are 12 sweeps across the tape per frame for 625i/25 containing data for 48 lines, 10 tracks for
525i/59.94
This format is not popular in 625i/25 countries because of the low chroma bandwidths.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software.
Sound sampling is locked to the video scans, so there is a guaranteed, integer, number of sound samples
per frame. |
| |
| DVCPRO50 |
Broadcast/Professional SDTV (D7) |
Panasonic |
| Medium |
1"/4 tape in cassette, 66.7mm/s (2 2/3" per second) |
| Standard |
SDTV (625i/25 and 525i/29.97) |
| Coding |
ITU-R BT.601 |
| Compression ratio |
3.3:1 |
Intra-frame DCT |
| Sampling |
4:2:2 |
| Data bits |
8 |
| Audio |
4 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
50Mb/s |
| Description |
Another development of the original DV format. The tape is used 100% faster than
DVCPRO25. Compression artefacts are much less visible than for all other variants of the DV format, and
performance is claimed to be similar to that of Digibeta.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software.
Sound sampling is locked to the video scans, so there is a guaranteed, integer, number of sound samples
per frame. |
| |
| DVCPROHD |
Broadcast HDTV (D21) |
Panasonic |
| Medium |
1"/4 tape in cassette, 135.4 mm/s (5 1/3" per second) |
| Standard |
HDTV (1080 i/25, psf/25, i/29,97, psf/29.97 and 720 p/50, p/59.94, p/60) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
6.3:1 (50Hz), 6.7:1(60Hz) |
Intra-frame DCT |
| Sampling |
4:2:2 |
1440x1080, 960x720 |
| Data bits |
8 |
| Audio |
8 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
100Mb/s |
| Description |
A further development of the original DV format. The tape is used 100%
faster than DVCPRO50. Compression artefacts are more visible than for all other variants of the DV format,
and performance is greatly affected by camera settings.
There are two variants, for 1080-line and 720-line HDTV:
1080-line variant records at both 50 and 59.94Hz field rates, but the compression ratio
changes a little between them, implying that compression artefacts should be less visible at 50Hz.
Although the 1080-line HDTV standard is always interlaced, the cameras can be set to shoot interlaced or
progressive (psf), and the signal travels correctly through the interlaced system without loss of vertical
resolution. Note that the video is not recorded at full resolution, the luma (and chroma) is sub-sampled
to 1440-pixel width for recording. However, the HDSDI output is correctly formatted for the 1920x1080
raster, but clearly with reduced detail content.
720-line variant records only at 59.94 or 60Hz, and is always progressive. The format
is mostly used in the Panasonic Varicam (AJ-HDC27F and H), which records at a constant speed of 60 or
59.94Hz, but the camera can be set to shoot at any speed between 4 and 60Hz (or 59.94), the tape
recording duplicates of the most recent frame until a fresh one is available from the camera. This
allows, on replay when the duplicated frames have been removed, the user to use "under-" and
"over-cranking", very useful for wildlife videography. When Varicam footage is replayed for ingest into
an editing system, it must be played through a "frame-rate converter", a special computer which ingests
the whole footage, and outputs only the fresh frames up-scaled to 1080-line via HDSDI.
Most DVCPROHD players include a reasonably good down-converter to deliver SDTV through SDI or composite,
although most broadcasters will not accept SDTV derived in this way because of aliasing. |
| |
| HDV 1080 |
Consumer HDTV |
Not Panasonic |
| Medium |
1"/4 tape in cassette, tracks are 10μm wide, 19.48mm/sec (0.75"/sec) |
| Standard |
HDTV (1080 i/25, psf/25, i/29.97, psf/29.97) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
MPEG2 (MP@H-14), long GoP |
Intra-frame DCT |
| Sampling |
4:2:0 |
1440x1080 |
| Data bits |
8 |
| Audio |
2 channel 384kb/s
48kHz clock rate
16-bit |
| Data rate |
25Mb/s |
| Description |
A development of the original DV format. The tape is used at the same
rate as ordinary DV, by advancing the tape 10 μm per track. Tapes for HDV are made to a higher
standard than for DV, because the risk of loss through dropouts is much greater (a drop-out in HDV can
affect 12 or more frames on tape). Compression artefacts are plainly visible on difficult pictures, and
most HDV camcorders do not deliver pictures that use the compression system to best effect, aliasing is
common.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software. The data transferred is the MPEG2 compressed stream.
HDV is not generally acceptable as a broadcast standard, although it is popular in semi-professional
circles. |
| |
| HDV 720 |
Consumer HDTV |
Not Panasonic |
| Medium |
1"/4 tape in cassette, tracks are 10μm wide, 19.48mm/sec (0.75"/sec) |
| Standard |
HDTV (720 p/25, p/29/97, p/50, p/59.94) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
MPEG2 (MP@H-14), long GoP |
Intra-frame DCT |
| Sampling |
4:2:0 |
1280x720 |
| Data bits |
8 |
| Audio |
2 channel 384kb/s
48kHz clock rate
16-bit |
| Data rate |
19Mb/s |
| Description |
A development of the original DV format. The tape is used at the same
rate as ordinary DV, by advancing the tape 10 μm per track. Tapes for HDV are made to a higher
standard than for DV, because the risk of loss through dropouts is much greater (a drop-out in HDV can
affect 12 or more frames on tape). Compression artefacts are plainly visible on difficult pictures, and
most HDV camcorders do not deliver pictures that use the compression system to best effect, aliasing is
common.
Note that the images are full resolution.
There are two variants of HDV 720, some cameras shoot and record 720p/25 (or 29.97) with a 6-frame GoP,
others record 720p/50 (or 59.94) with a 12-frame GoP. Generally, HDV 720 produces pictures with fewer
compression artefacts and less spatial aliasing than does HDV 1080, although the pictures are softer.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software. The data transferred is the MPEG2 compressed stream.
HDV is not generally acceptable as a broadcast standard, although it is popular in semi-professional
circles. |
| |
| HDCAM |
Broadcast HDTV (D11) |
Sony |
| Medium |
1"/2 tape in cassette |
| Standard |
HDTV 1080 (psf/23.98, psf/24, psf/25, psf/29.97, psf/30, i/25, i/29.97, i/30) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
About 4.3:1 |
Intra-frame DCT |
| Sampling |
3:1:1 |
1440x1080 |
| Data bits |
8 |
| Audio |
4 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
116Mb/s (psf/23.98) to 145Mb/s (psf/30 and i/30) |
| Description |
Standard HDTV workhorse recording system for many years. Compression is
relatively light, so compression artefacts are rare (but visible once you know what can cause them).
Widely accepted as being rugged and near-transparent, so multi-generation tape-to-tape editing has been
acceptable in the past, but no longer so as cameras and displays have improved.
The tape speed is altered with the video frame rate, so that the bit-density on tape is held constant.
Thus a tape labelled "40 minutes" will last 40 minutes at 30 frames per second, but lasts 48 minutes at
25. Some tapes are labelled with two durations to deal with this.
Note that the colour sampling is 3:1:1. Therefore the lines of chroma have only 480 pixels. This has been
done as a compromise between compression artefacts and bandwidth, but can result in pictures that are
quite visibly soft when highly saturated.
HDCAM players will often play all varieties of Betacam tapes, including analogue, and includes a
reasonably good down-converter to deliver SDTV through SDI or composite, although most broadcasters
will not accept SDTV derived in this way because of aliasing. Down-conversion will be to whichever of
the SDTV standards is most appropriate, but there will be no output if the tape is playing at 24 frames
per second (since there is no 24 Hz SDTV standard). |
| |
| XDCAM |
Professional/Semi-pro SDTV |
Sony |
| Medium |
Professional Disk (Blu-Ray) |
| Standard |
SDTV (625i/25 and 525i/29.97) |
| Coding |
ITU-R BT.601 |
| Compression ratio |
5:1 |
Intra-frame DCT |
| Sampling |
4:2:0 (625i/25), 4:1:1 (525i/29.97) |
| Data bits |
8 |
| Audio |
2 channel LPCM
48kHz clock rate
16-bit |
4 channel LPCM
32kHz
12-bit A law |
| Data rate |
25Mb/s |
| Description |
This records onto Professional Disk format (actually, BluRay disk), but
is otherwise identical to DVCAM. Compression artefacts are plainly visible on difficult pictures, but the
better semi-professional cameras have optical filters to remove the high video frequencies that would
otherwise cause problems.
Since recording is clip-based and not continuous, it is easier to "edit in the camera", and downloading
of footage into an editor is much more convenient than with tape.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software.
Sound sampling is locked to the video scans, so there is a guaranteed, integer, number of sound samples
per frame. |
| |
| XDCAM HD |
Professional/Semi-pro HDTV |
Sony |
| Medium |
Professional Disk (Blu-Ray) |
| Standard |
HDTV (1080 psf/23.98, psf/25, psf/29.97, i/25, i/59.94) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
5:1 |
Intra-frame DCT |
| Sampling |
4:2:0 |
1440x1080 |
| Data bits |
8 |
| Audio |
4 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
18Mb/s (LP), 25Mb/s (SP), 35Mb/s(HQ) |
| Description |
This records onto Professional Disk format (actually, BluRay disk), but
is otherwise identical to HDV 1080. Compression artefacts are plainly visible on difficult pictures at
the lower data rates, but may be acceptable at the highest.
Since recording is clip-based and not continuous, it is easier to "edit in the camera", and downloading
of footage into an editor is much more convenient than with tape.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software.
Sound sampling is locked to the video scans, so there is a guaranteed, integer, number of sound samples
per frame. |
| |
| XDCAM EX |
Professional/Semi-pro HDTV |
Sony |
| Medium |
Solid state, SxS card |
| Standard |
HDTV (1080 psf/23.98, psf/25, psf/29.97, i/25, i/59.94) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
5:1 |
Intra-frame DCT |
| Sampling |
4:2:0 |
1440x1080 |
| Data bits |
8 |
| Audio |
4 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
18Mb/s (LP), 25Mb/s (SP), 35Mb/s(HQ) |
| Description |
This records onto solid state memory cards, but is otherwise identical to
XDCAM HD. Compression artefacts are plainly visible on difficult pictures at the lower data rates, but
may be acceptable at the highest.
Since recording is clip-based and not continuous, it is easier to "edit in the camera", and downloading
of footage into an editor is much more convenient than with tape.
Ingestion into a video editing system is simple, but since the cost of cards is high, there is a motive
for using a minimal number of cards in the field, and to transfer the video data to intermediate stores
so that the cards can be reused.
Camcorders usually have a SDTI interface, designated IEEE1394, for easy downloading of footage into
editing software.
Sound sampling is locked to the video scans, so there is a guaranteed, integer, number of sound samples
per frame. |
| |
| P2 |
Broadcast HDTV |
Panasonic |
| Medium |
P2 cards |
| Standard |
HDTV (1080 i/25, psf/25, i/29,97, psf/29.97 and 720 p/50, p/59.94, p/60) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
6.3:1 (50Hz), 6.7:1(60Hz) |
Intra-frame DCT |
| Sampling |
4:2:2 |
1440x1080, 960x720 |
| Data bits |
8 |
| Audio |
8 channel LPCM
48kHz clock rate
16-bit |
| Data rate |
100Mb/s |
| Description |
This records compressed video onto solid state P2 cards, each card
contains 4 SD cards, selected for high-speed operation. Otherwise, the format is the same as DVCPROHD,
but files are saved in MXF format.
Note that the video is not recorded at full resolution, the luma (and chroma) is sub-sampled to 1440- or
960-pixel width for recording.
However, the HDSDI output is correctly formatted for the 1920x1080 or 1280x720 raster, but clearly with
reduced detail content.
Ingestion into a video editing system is simple, but since the cost of cards is high, there is a motive
for using a minimal number of cards in the field, and to transfer the video data to intermediate stores
so that the cards can be reused. |
| |
| AVCHD |
Consumer HDTV |
Panasonic, Sony |
| Medium |
Solid state storage |
| Standard |
HDTV (1080 p/24, i/25, psf/25, i/29.97, psf/29.97, and 720 p/24, p/50, p/59.94), SDTV (625i/25, 252i/29.97) |
| Coding |
ITU-R BT.601 (STDV), ITU-R BT.709 (HDTV) |
| Compression ratio |
MPEG4 H.264 |
| Sampling |
4:2:0 |
1920x1080p/24, 1440x1080 1280x720, 720x576, 720x480 |
| Data bits |
8 |
| Audio |
2 channel, AC-3 (HDTV) LPCM (SDTV)
48kHz clock rate
16-bit |
| Data rate |
24Mb/s, 18Mb/s for DVD recording |
| Description |
This is a "next-generation" format for consumer camcorders. It aims at
the DV market but with considerably higher quality. As yet, there are few camcorders using it, and so it
is not possible to give a sensible verdict on its performance. |
| |
| AVC-I 50 |
Professional/Semi-pro HDTV |
Panasonic |
| Medium |
Solid state storage |
| Standard |
HDTV (1080 p/24, i/25, psf/25, i/29.97, psf/29.97, and 720 p/24, p/50, p/59.94) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
MPEG4 H.264, I-frames only |
Intra-frame |
| Sampling |
4:2:0 |
1440x1080, 960x720 |
| Data bits |
10 |
| Data rate |
50Mb/s |
| Description |
This is a "next-generation" format for professional camcorders. It aims
beyond the DV market but with considerably higher quality. As yet, there are few camcorders using it, and
so it is not possible to give a sensible verdict on its performance. In theory, this could be as good as
DVCPROHD or better since it is 10-bit video, but the 4:2:0 subsampling is a problem for much
production. |
| |
| AVC-I 100 |
Broadcast HDTV |
Panasonic |
| Medium |
Solid state storage |
| Standard |
HDTV (1080 p/24, i/25, psf/25, i/29.97, psf/29.97, and 720 p/24, p/50, p/59.94) |
| Coding |
ITU-R BT.709 |
| Compression ratio |
MPEG4 H.264, I-frames only |
Intra-frame |
| Sampling |
4:2:2 |
1920x1080, 1280x720 |
| Data bits |
10 |
| Data rate |
100Mb/s |
| Description |
This is a "next-generation" format for broadcast camcorders. It aims at
the HDCAM and DVCPROHD market but with considerably higher quality. As yet, there are few camcorders
using it, and so it is not possible to give a sensible verdict on its performance. In theory this should
be better than either HDCAM or DVCPROHD, since it is full resolution, 10-bit, and 4:2:2. It could be the
HDTV equivalent of Digibeta. |