hd
ASCII, decimal, hexadecimal, octal dump
see also :
gdb - od
Synopsis
hexdump
[-bcCdovx]
[-e format_string]
[-f format_file]
[-n length]
[-s skip] file ...
hd [-bcdovx]
[-e format_string]
[-f format_file]
[-n length]
[-s skip] file ...
add an example, a script, a trick and tips
examples
Display the input in perusal format:
"%06.6_ao " 12/1 "%3_u "
"\t\t" "%_p "
"\n"
Implement the -x option:
"%07.7_Ax\n"
"%07.7_ax " 8/2 "%04x " "\n"
Some examples for the -e option:
# hex bytes
% echo hello | hexdump -v -e ’/1 "%02X "’ ; echo
68 65 6C 6C 6F 0A
# same, with ASCII section
% echo hello | hexdump -e ’8/1 "%02X ""\t"" "’ -e ’8/1
"%c""\n"’
68 65 6C 6C 6F 0A hello
# hex with preceding ’x’
% echo hello | hexdump -v -e ’"x" 1/1 "%02X" " "’ ; echo
x68 x65 x6C x6C x6F x0A
# one hex byte per line
% echo hello | hexdump -v -e ’/1 "%02X\n"’
68
65
6C
6C
6F
0A
# a table of byte#, hex, decimal, octal, ASCII
% echo hello | hexdump -v -e ’/1 "%_ad# "’ -e ’/1 "%02X hex"’ -e
’/1 " = %03i dec"’ -e ’/1 " = %03o oct"’ -e ’/1 " = _%c\_\n"’
0# 68 hex = 104 dec = 150 oct = _h_
1# 65 hex = 101 dec = 145 oct = _e_
2# 6C hex = 108 dec = 154 oct = _l_
3# 6C hex = 108 dec = 154 oct = _l_
4# 6F hex = 111 dec = 157 oct = _o_
5# 0A hex = 010 dec = 012 oct = _
_
# byte# & ASCII with control chars
% echo hello | hexdump -v -e ’/1 "%_ad# "’ -e ’/1 "
_%_u\_\n"’
0# _h_
1# _e_
2# _l_
3# _l_
4# _o_
5# _lf_
source
What should I upgrade on my Linux media PC to stop 1080p video issues?
Video card. Get an nVidia card with the highest VDPAU
set.
Check this table to find a card which fits your need. (You
don't have to spend too much, even the newer, low-performance
cards are perfect to play back the highest definition. Like
GT240 at the moment.)
You will play your movies with vdpau this way.
(You may need this PPA later, when you install the card, in
order to install the necessary software support. PPAs are for
Ubuntu, they stand for a personal package archive. However, I
used many Linux distributions, and every distro ships with vdpau
support nowadays.)
source
720p videos get choppy and freeze constantly when played on my netbook
vlc does not use gpu acceleration as a default, and even when
activated it's experimental as of now. Check http://wiki.videolan.org/VLC_GPU_Decoding for
prerequisites and codecs.
Assuming it's not activated your cpu (netbook = atom?) most
likely has difficulties to keep pace.
Have you tried mplayer?
source
Do Intel HD 3000 Graphics run out of the box on Linux?
Ubuntu 11.04 beta seems to support the graphics drivers out of
the box, as per this discussion.
As an opinion for game, here's a quote from the same discussion
I am getting stutter in some games, which are mainly in wine,
or java (minecraft).
source
Which camera i can use in my laptop to have more better quality then Iphone tiny camera?
- Note: This is a shopping question BUT this is NOT a shopping
answer per se. It is a "do your homework as well as you can
before asking and you will get better results, and here is how to
do it and why you want to" type answer :-). As such it is
applicable to both shopping and technical questions and may (or
may not) have a place here.
The technically competent may enjoy the last two references.
This is very very much a shopping type question. It doesn't need
to be. This is probably not the right place for the question
regardless, but you would help yourself by learning how to ask it
better. (Questions that relate to "shopping" re electronic design
decisions have their place here, I think (fwiw)).
In this case (and in most cases) if you do your homework BEFORE
asking questions like this you will be better able to judge if
the answers are good ones.
Note that high megapixels and high photo quality are not
identical - BUT you asked in terms of megapixels. If you are not
100% sure that a feature such as megapixels is directly related
to another attribute such as quality then you should be
exceptionally careful about talking about one when you mean the
other. eg the Sony A850 & A950 DSLR cameras have 24+ MP sensors
and produce the most detailed studio shots available from a 35mm
DSLR camera. But if you take photos on low light or focus on (pun
almost intended) sports photography then a 12 MP Nikon D700 or
the even better D800s will produce vastly superior "quality". So,
here, 12 MP >> 24 MP for "quality".
The "clear" answer to your question is:
- "The camera that you can find advertised that you consider is
much better then the one on an iphone because you understand the
differences - and which has 1080p video, and AVCHD and/or 50p or
60p rating, and which has the highest possible megapixel rating
for still shots (probably in the 12-20 MP range, but maybe
higher)." Whew!
While this answer has replaced your general terms with "buzz
words" / jargon they are the sort of terms that you are going to
underatnd at least a little in order to make a good choice. If
you ask general questions, as you have done, without doing any
homework re the terminology used and the facilities available,
you run the severe risk of accepting a recommendation that is
uninformed and that does not meet your needs as well as they
could have been met.
- eg "What is the difference between (720i), 720p, 1080i,
1080p, what do these terms mean, and why should you care?. And do
you care?"
A little searching will produce comments like:
- The AVCHD video format specification has been updated to
include 1080 60p and 50p video. The AVCHD 2.0 standard has been
approved by Sony and Panasonic - the co-promoters of the format.
The move also includes additional support for high definition 3D
movies in the format. Up until now, both companies have made
high-end camcorders that incorporated out-of-specification 60p
video in what was otherwise an AVCHD arrangement.
Which will help guide further searching as you begin to better
understand the subject.
Research 1080p (and the others mentioned above - you want 1080p)
Research 50p, 60p, AVCHD - what you want is less certain. But
when you have finished you will know what you want and why.
So, all that said, the following may give you a good start on
your quest:
-
720p - 720 lines of video - better quality than "TV"
-
1080i / 1080p - 1080 lines of video - better quality than
720. You want 1080p - see below.
-
xxxi = interlaced - picture is delivered in two consecutive
"frames" each having half the information. Standard TV does
this. Lower cost to implement and to transmit. Has "issues"
Avoid.
-
xxxp = non interlaced. All picture information in one
"frame". Better quality. Buy it
-
50p / 60p = 50 or 60 frames per second. Faster than TV (50i
or 60i) or "standard " video 30x (or film at 24fps but a
whole new (vast) subject). 50p for 50 Hz mains areas (eg UK).
60p for 60 Hz mains areas (eg USA). Much better potenr=tial
motion handling and slo-mo and ... than 30p etc.
-
AVCHD Wikipedia - AVCHD. http://en.wikipedia.org/wiki/AVCHD
Also:
Steven says this looks better - Search the web for 1080p 50p 60p:
24p
1080p 50p samples. Wow. Note that the 1080
affects the resolution and the xxxxp and 50p affect the motion
handling.
50p and slow motion playing
Brain hurting time :-) 24PA, 24F, 24P, 25F,
25P, 30F, 30P explained
Deep magic. Only for techo-freaks
source
Video playback shows fault lines where it looks like parts of two frames are being spliced together (edit: called "tearing")
This doesn't look like an issue with any specific frame. Rather,
it's probably your video card being too overwhelmed to display
the video without lagging. Do you notice more tearing with
higher-resolution videos? More pixels means more work for your
hardware. High framerates can cause also more work, as it has
less time to process all those tiny pixels in a given frame.
You should try experimenting with different Video Output drivers.
IDK about VLC, but Mplayer does best with XV. If you and use XV
with so-called "adaptors", that may help improve your performance
even further (eg, -vo xv:adaptor=0). If you still experience
tearing, you can try using software scaling to reduce the
resolution (-vf-add scale=720), if you have a fast CPU.
If all of the above fails, your GPU probably just plain isn't
fast enough for HD video. You could try buying a newer, faster
model. Or, you could probably use a video converter program, such
as FFMpeg, to
convert the video at a lower resolution. If you don't like
command-lines, you could also use XMedia-Recode (a Windows-based
GUI), as it works quite well with WINE. The homepage is in German, but you can download it
from Video Help, if you feel more comfortable getting
it from an English site. Either way, XMR will work in English.
source
Is there ultra HD support in Linux?
As Linux uses X11 to do graphical rendering, this question is
really about whether X11 supports it.
The answer is yes, X11 supports arbitrary sizes. One example with
4K HD is here.
description
The hexdump utility is a
filter which displays the specified files, or the standard
input, if no files are specified, in a user specified
format.
The options are
as follows:
-b
One-byte
octal display. Display the input offset in hexadecimal,
followed by sixteen space-separated, three column,
zero-filled, bytes of input data, in octal, per line.
-c
One-byte
character display. Display the input offset in
hexadecimal, followed by sixteen space-separated, three
column, space-filled, characters of input data per line.
-C
Canonical
hex+ASCII display. Display the input offset in
hexadecimal, followed by sixteen space-separated, two
column, hexadecimal bytes, followed by the same sixteen
bytes in %_p format enclosed in
’’|’’ characters.
Calling the
command hd implies this option.
-d
Two-byte
decimal display. Display the input offset in
hexadecimal, followed by eight space-separated, five column,
zero-filled, two-byte units of input data, in unsigned
decimal, per line.
-e
format_string
Specify a format string to be
used for displaying data.
-f
format_file
Specify a file that contains
one or more newline separated format strings. Empty lines
and lines whose first non-blank character is a hash mark
(#) are ignored.
-n
length
Interpret only length
bytes of input.
-o
Two-byte
octal display. Display the input offset in hexadecimal,
followed by eight space-separated, six column, zero-filled,
two byte quantities of input data, in octal, per line.
-s
offset
Skip offset bytes from
the beginning of the input. By default, offset is
interpreted as a decimal number. With a leading 0x or
0X, offset is interpreted as a hexadecimal
number, otherwise, with a leading 0, offset is
interpreted as an octal number. Appending the character
b, k, or m to offset causes it
to be interpreted as a multiple of 512, 1024, or 1048576,
respectively.
-v
Cause
hexdump to display all input data. Without the
-v option, any number of groups of output
lines, which would be identical to the immediately preceding
group of output lines (except for the input offsets), are
replaced with a line comprised of a single asterisk.
-x
Two-byte
hexadecimal display. Display the input offset in
hexadecimal, followed by eight, space separated, four
column, zero-filled, two-byte quantities of input data, in
hexadecimal, per line.
For each input
file, hexdump sequentially copies the input to
standard output, transforming the data according to the
format strings specified by the -e and
-f options, in the order that they were
specified.
Formats
A format string contains any number of format units,
separated by whitespace. A format unit contains up to three
items: an iteration count, a byte count, and a format.
The iteration
count is an optional positive integer, which defaults to
one. Each format is applied iteration count times.
The byte count
is an optional positive integer. If specified it defines the
number of bytes to be interpreted by each iteration of the
format.
If an iteration
count and/or a byte count is specified, a single slash must
be placed after the iteration count and/or before the byte
count to disambiguate them. Any whitespace before or after
the slash is ignored.
The format is
required and must be surrounded by double quote ("
") marks. It is interpreted as a fprintf-style format
string (see fprintf(3)), with the following exceptions:
•
An asterisk (*) may not be used
as a field width or precision.
•
A byte count or field precision
is required for each ’’s’’
conversion character (unlike the fprintf(3) default which
prints the entire string if the precision is
unspecified).
•
The conversion characters
’’%’’,
’’h’’,
’’l’’,
’’n’’, ’’p’’
and ’’q’’ are not supported.
•
The single character escape
sequences described in the C standard are supported:
NUL \0
<alert character> \a
<backspace> \b
<form-feed> \f
<newline> \n
<carriage return> \r
<tab> \t
<vertical tab> \v
The
hexdump utility also supports the following
additional conversion strings:
_a[dox]
Display the
input offset, cumulative across input files, of the next
byte to be displayed. The appended characters d,
o, and x specify the display base as decimal,
octal or hexadecimal respectively.
_A[dox]
Identical to
the _a conversion string except that it is only
performed once, when all of the input data has been
processed.
_c
Output
characters in the default character set. Nonprinting
characters are displayed in three character, zero-padded
octal, except for those representable by standard escape
notation (see above), which are displayed as two character
strings.
_p
Output
characters in the default character set. Nonprinting
characters are displayed as a single
’’.’’.
_u
Output US ASCII
characters, with the exception that control characters are
displayed using the following, lower-case, names. Characters
greater than 0xff, hexadecimal, are displayed as hexadecimal
strings.
000 NUL
001 SOH 002 STX 003 ETX 004 EOT
005 ENQ
006 ACK 007 BEL 008 BS 009 HT
00A LF 00B VT
00C FF 00D CR 00E SO 00F SI 010 DLE
011 DC1
012 DC2 013 DC3 014 DC4 015 NAK
016 SYN 017 ETB
018 CAN 019 EM 01A SUB 01B ESC
01C FS 01D GS
01E RS 01F US 07F DEL
The default and
supported byte counts for the conversion characters are as
follows:
%_c, %_p, %_u, %c
One byte counts
only.
%d, %i, %o, %u, %X, %x
Four byte
default, one, two and four byte counts supported.
%E, %e, %f, %G, %g
Eight byte
default, four and twelve byte counts supported.
The amount of
data interpreted by each format string is the sum of the
data required by each format unit, which is the iteration
count times the byte count, or the iteration count times the
number of bytes required by the format if the byte count is
not specified.
The input is
manipulated in ’’blocks’’, where a
block is defined as the largest amount of data specified by
any format string. Format strings interpreting less than an
input block’s worth of data, whose last format unit
both interprets some number of bytes and does not have a
specified iteration count, have the iteration count
incremented until the entire input block has been processed
or there is not enough data remaining in the block to
satisfy the format string.
If, either as a
result of user specification or hexdump modifying the
iteration count as described above, an iteration count is
greater than one, no trailing whitespace characters are
output during the last iteration.
It is an error
to specify a byte count as well as multiple conversion
characters or strings unless all but one of the conversion
characters or strings is _a or _A.
If, as a result
of the specification of the -n option or
end-of-file being reached, input data only partially
satisfies a format string, the input block is zero-padded
sufficiently to display all available data (i.e., any format
units overlapping the end of data will display some number
of the zero bytes).
Further output
by such format strings is replaced by an equivalent number
of spaces. An equivalent number of spaces is defined as the
number of spaces output by an s conversion character
with the same field width and precision as the original
conversion character or conversion string but with any
’’+’’,
’’ ’’,
’’#’’ conversion flag characters
removed, and referencing a NULL string.
If no format
strings are specified, the default display is equivalent to
specifying the -x option.
exit status
The hexdump and hd utilities exit 0 on
success, and >0 if an error occurs.
see also
gdb , od
BSD
February 18, 2010 BSD