Trying to read the sizes of disks that were created in multiple sessions using GetDiskFreeSpaceEx() gives the size of the last session only. How do I read correctly the number and sizes of all sessions in C/C++?
Thanks.
You might want to look at the DeviceIoControl API function. See here for control codes. Here is a code example that retrieves the size of a CD disk. Substitute
CreateFile(TEXT("\\\\.\\PhysicalDrive0")
for e.g.
CreateFile(TEXT("\\\\.\\F:") /* Drive is F: */
if you wish.
Note: The page says that DeviceIoControl can be used to "retrieve information about a floppy disk drive, hard disk drive, tape drive, or CD-ROM drive", but I have also tested it on a DVD, and it seemed to work perfectly. I did not have access to any multisession DVDs to test, so you'll have to test if that works yourself. If it doesn't work, I'd try some of the other control codes, at least IOCTL_DISK_GET_DRIVE_GEOMETRY_EX, IOCTL_DISK_GET_DRIVE_LAYOUT_EX, IOCTL_DISK_GET_LENGTH_INFO and IOCTL_DISK_GET_PARTITION_INFO_EX.
If all fails with DeviceIoControl, you could possibly make use of the Windows Image Mastering API (IMAPI). You'll need v2 of the API (included with Vista & later, can be added to XP & 2003 too, see here: What's new in IMAPIv2) for DVD support. This API is primarily for CD burning, but does perhaps contain some functionality for retrieving disk size, I'd find it weird if it didn't. Particularly, this example seems to be interesting. I do not know if this one works for multisession disks either, but since it can create them, I guess it's likely.
Here are some resources for IMAPI:
MSDN - IMAPI
MSDN - IMAPI interfaces
MSDN - Creating multisession disks with IMAPI (note: example with VB, not C or C++)
Hey I got at least 2 solutions for you:
1) Download dvd+rw-mediainfo.exe from http://fy.chalmers.se/~appro/linux/DVD+RW/tools/win32/, it's a tool that reads info about your disc. Then just make a system call from your app and parse the results. Here's example output:
D:\Downloads>"dvd+rw-mediainfo.exe" f:
INQUIRY: [HL-DT-ST][DVDRAM GT30N ][1.01]
GET [CURRENT] CONFIGURATION:
Mounted Media: 10h, DVD-ROM
Current Write Speed: 1.0x1385=1385KB/s
Write Speed #0: 8.0x1385=11080KB/s
Write Speed #1: 4.0x1385=5540KB/s
Write Speed #2: 2.0x1385=2770KB/s
Write Speed #3: 1.0x1385=1385KB/s
Speed Descriptor#0: 00/2292991 R#8.0x1385=11080KB/s W#8.0x1385=11080KB/s
READ DVD STRUCTURE[#0h]:
Media Book Type: 01h, DVD-ROM book [revision 1]
Legacy lead-out at: 2292992*2KB=4696047616
READ DISC INFORMATION:
Disc status: complete
Number of Sessions: 1
State of Last Session: complete
Number of Tracks: 1
READ TRACK INFORMATION[#1]:
Track State: complete
Track Start Address: 0*2KB
Free Blocks: 0*2KB
Track Size: 2292992*2KB
Last Recorded Address: 2292991*2KB
FABRICATED TOC:
Track#1 : 17#0
Track#AA : 17#2292992
Multi-session Info: #1#0
READ CAPACITY: 2292992*2048=4696047616
2) Investigate mciSendString from [DllImport("winmm.dll", EntryPoint = "mciSendStringA", CharSet = CharSet.Ansi)], I suspect you can send some command and get the desired results.
PS: of course you may download dvd+rw-mediainfo.exe sources from here and investigate further, I am just giving you ideas to think of.
UPDATE
Link to source code updated, thanks #oystein
There are many way to do this since the DVD drives have several interfaces for this due to legacy and backward-compatibility issues.
You could send an IOCTL_SCSI_PASSTHROUGH_DIRECT command to the DVD-drive ( the physicaldevice handle for it). With it you issue a SCSI commands that will be answered by the drive. You can read session information, disk information disk capcity and more.
I believe that dvd+rw-mediainfo.exe issues these.
Unfortunatly, the interface is a bit tricky and obscure, since it is a command within a command. Th passthrough has a byte buffer you will have to fill in yourself with the command structure.
Or you can call IOCTL_CDROM_READ_TOC_EX:
http://www.osronline.com/ddkx/storage/k306_2cs2.htm
I also believe that the exact set of the IOCTL / commands that will work depends on on the drive and its firmaware.
Older drives will not support the newr interfaces and some of the newer drives will not support legacy interfaces.
Thus, some of the libraries & tools might use one or more of these interfaces.
Accseeing the older sessons is all quite messy, really, since most OS will not care about them, only the most recent ones.
Related
Background: I was testing a nfs-server with fio. And I find that no matter how much "iodepth" is set to fio. The nfs-server can only have "64 Inflight". So I just suspect that somewhere around "nfs protocol" limits the max concurrent(max io in flight).
fio command is
fio -numjobs=1 -iodepth=128 -direct=1 -ioengine=libaio -sync=1 -rw=write -bs=4k -size=500M -time_based -runtime=90 -name=Fiow -directory=/75
My nfs-server is based on ganesha, and got conclusion "64 Inflight" by using ganesha_stats.py.
So I have two options for now:
Study the calling-graph and read code to find the problem
I download linux kernel code, but struggle to . Which function/source file should I begin , maybe vfs.c:nfsd_write?
Tried to use 'perf' to trace calling-graph to speed up my code reading tour for linux kernel, but failed. Because 'perf report' shows shared library symbol without function name.
Learn the nfs protocol/mount cmd to seek the limit.
Can somebody can help me with this? :)
Assuming you're using NFSv4.1 (RFC 5661):
In NFSv4.1, the number of outstanding requests is bounded by the size of the slot table [...].
And in Linux:
#define NFS4_DEF_SLOT_TABLE_SIZE (64U)
It is the default for this module param:
module_param(max_session_slots, ushort, 0644);
MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
"requests the client will negotiate");
IIUC the total maximum for this is:
#define NFS4_MAX_SLOT_TABLE (1024U)
I am looking for a way to receive as an input any video (that is supported on iOS) and save on the device a new video with a new Frame Per Second rate. The motivation is to decrease the video size, and as well make it as lite weighted as possible.
Tried using ffmpeg library from command line (need it to run directly from application)
Tried working with SDAVAssetExportSessionDelegate, but managed only to change the bit per second (each frame quality is lower)
Though to work with OpenCV - but preferring something lighter and build in if possible
Objective C:
'''
compressionEncoder.videoSettings = #
{
AVVideoCodecKey: AVVideoCodecTypeH264,
AVVideoWidthKey: [NSNumber numberWithInt:width], //Set your resolution width here
AVVideoHeightKey: [NSNumber numberWithInt:height], //set your resolution height here
AVVideoCompressionPropertiesKey: #
{
AVVideoAverageBitRateKey: [NSNumber numberWithInt:bitRateKey], // Give bitrate for lower size low values
AVVideoProfileLevelKey: AVVideoProfileLevelH264High40,
// Does not change - quality setting and not reletaed to playback framerate!
//AVVideoMaxKeyFrameIntervalKey: #800,
},
};
compressionEncoder.audioSettings = #
{
AVFormatIDKey: #(kAudioFormatMPEG4AAC),
AVNumberOfChannelsKey: #2,
AVSampleRateKey: #44100,
AVEncoderBitRateKey: #128000,
};
'''
Expected a video with less Frame Per Second, each frame is in the same quality. Similar to a brief thumbnail summary of the video
The type of conversion you are doing will be time and power consuming on a mobile device, but I am guessing you are already aware of that.
Given your end goal is to reduce size, while presumably maintaining a reasonable quality, you may find you want to experiment with different settings etc in the encodings.
For this type of video manipulation, ffmpeg is a good choice as you probably saw from your command line usage. To use ffmpeg from an application, a common approach is to use a well supported 'ffmpeg wrapper' - this effectively runs the Ffmpeg command line commands from wihtin your application.
The advantage is that all the usual syntax should work and you can leverage the vast amount of info on ffmpeg command line syntax on the web. The downsides are that ffmpeg was not not designed to be wrapped like this so you may see some issues, although with a well supported wrapper you should find either help or that others have already worked around the issues.
Some examples of popular iOS ffmpeg wrappers:
https://github.com/tanersener/mobile-ffmpeg
https://github.com/sunlubo/SwiftFFmpeg
Get MobileFFMpeg up and running:
https://stackoverflow.com/a/59325680/1466453
Once you can make MobileFFMpeg calls in your IOS code then changing frame rate is pretty straightforward with this code:
[MobileFFmpeg execute: #"-i -filter:v fps=fps=30 "];
I am trying to programmatically track the amount of data in my receive buffer. I am receiving UDP data. After doing some research it seems that the only way to do this in Linux is to look at /proc/net/udp. This seems like a good solution until I realized that two applications could be listening to the same multicast group and I need to tell them apart. It seems that I am supposed to do this by determining what my inode is.
I spend some time looking into this and there are suggestions that sockfd_lookup or sock_from_file is the way to go but on my CentOS Linux machine, these functions do not seem to be available.
Can someone please help me to figure out which line in /proc/net/udp belongs to my application?
I started using the ioctl (handle, FIONREAD, &bytesInBuffer) call only to discover that in Linux this only returns the size of the first datagram packet in the buffer.
Google seems to suggest that the sockfd_lookup call can be used to get the inode but a grep in my /usr/local/include/ does not return these functions.
My linux/net.h seems pretty bare-bone compared to some I can find on google which includes structs like "socket" which has the sock member which I believe has the inode information. My linux/net.h on CentOs only is 58 lines long and has only a few #defines and an enum.
after a bit of fiddling I noticed that readlink("/proc/self/fd/$fd") (under Linux 5.3) gives me something like:
socket:[3753088]
back. I can parse this and use the resulting digits to look up the relevant line in /proc/net/udp:
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode ref pointer drops
2867: 00000000:0BB8 00000000:0000 07 00000000:00000000 00:00000000 00000000 1000 0 3753088 2 000000003ae8e911 0
that said, I don't understand why you'd want to do this, but never mind!
I'm also not sure why you don't just look up by sock&peer name, which might be easier
I need a library for my C++ program.
But the problem, I don't know the name of this data type I want.
I have NPAPI plugin (I know this API is deprecated and removed from modern browsers) which issues to a server
HTTP range requests. Request is asyncronious and the data may arraive in any order with any chunks size.
So I need to track ranges I already have requested from a server.
For example, if initially I requested bytes [10-20] (inclusevely), then I requested [30-40] the data type I need should keep it as two intervals:
[10-20],[30-40]
But if I request [21-29] or even [15-35] it should be merged in one interval:
[10-20],[30-40] + [15-35] = [10-40]
Also I need a substraction when a requested block arrives:
[10-40] - [20-30] = [10-19],[31-40]
(requested - arrived = we're still waiting for)
I had a look at boost::numeric::intervals library but at first glance it is too big for this task (1583 files, 13 Mb of sources after './dist/bin/bcp numeric/interval ~/boost').
Also, GNU ddrescue has some similar arithmetics inside but the code isn't a library there, it coupled too much with the applications specifics.
UPDATE:
Here is what I've found on my way:
A container for integer intervals, such as RangeSet, for C++
https://en.wikipedia.org/wiki/Interval_tree
Boost.ICL
NCBI C++ Toolkit, CIntervalTree
I recently starting working with OpenCV with the intent of stitching large amounts of images together to create massive panoramas. To begin my experimentation, I looked into the sample programs that come with the OpenCV files to get an idea about how to implement the OpenCV libraries. Since I was interested in image stitching, I went straight for the "stitching_detailed.cpp." The code can be found at:
https://code.ros.org/trac/opencv/browser/trunk/opencv/samples/cpp/stitching_detailed.cpp?rev=6856
Now, this program does most of what I need it to do, but I ran into something interesting. I found that for 9 out of 15 of the optional projection warpers, I receive the following error when I try to run the program:
Insufficient memory (Failed to allocate XXXXXXXXXX bytes) in unknown function,
file C:\slave\winInstallerMegaPack\src\opencv\modules\core\src\alloc.cpp,
line 52
where the "X's" mark integer that change between the different types of projection (as though different methods require different amounts of space). The full source code for "alloc.cpp" can be found at the following website:
https://code.ros.org/trac/opencv/browser/trunk/opencv/modules/core/src/alloc.cpp?rev=3060
However, the line of code that emits this error in alloc.cpp is:
static void* OutOfMemoryError(size_t size)
{
--HERE--> CV_Error_(CV_StsNoMem, ("Failed to allocate %lu bytes", (unsigned long)size));
return 0;
}
So, I am simply lost as to the possible reasons that this error may be occurring. I realize that this error would normally occur if the system is out of memory, but I when running this program with my test images I am never using more that ~3.5GB of RAM, according to my Task Manager.
Also, since the program was written as an sample of the OpenCV stitching capabilities BY OpenCV developers I find it hard to believe that there is a drastic memory error present within the source code.
Finally, the program works fine if I use some of the warping methods:
- spherical
- fisheye
- transverseMercator
- compressedPlanePortraitA2B1
- paniniPortraitA2B1
- paniniPortraitA1.5B1)
but as ask the program to use any of the others (through the command line tag
--warp [PROJECTION_NAME]):
- plane
- cylindrical
- stereographic
- compressedPlaneA2B1
- mercator
- compressedPlaneA1.5B1
- compressedPlanePortraitA1.5B1
- paniniA2B1
- paniniA1.5B1
I get the error mentioned above. I get pretty good results from the transverseMercator project warper, but I would like to test the stereographic in particular. Can anyone help me figure this out?
The pictures that I am trying to process are 1360 x 1024 in resolution and my computer has the following stats:
Model: HP Z800 Workstation
Operating System: Windows 7 enterprise 64-bit OPS
Processor: Intel Xeon 2.40GHz (12 cores)
Memory: 14GB RAM
Hard Drive: 1TB Hitachi
Video Card: ATI FirePro V4800
Any help would be greatly appreciated, thanks!
When I run OpenCV's APP traincascade, i get just the same error as you:
Insufficient memory (Failed to allocate XXXXXXXXXX bytes) in unknown function,
file C:\slave\winInstallerMegaPack\src\opencv\modules\core\src\alloc.cpp,
line 52
at the time, only about 70% pecent of my RAM(6G) was occupied. And when runnig trainscascade step by step, I found that the error would be thrown.when it use about more than 1.5G RAM space.
then, I found the are two arguments which can control how many memory should be used:
-precalcValBufSize
-precalcIdxBufSize
so i tried to set these two to 128, it run. I hope my experience can help you.
I thought this problem is nothing about memory leak, it is just relate to how many memory the OS limits a application occupy. I expect someone can check my guess.
I've recently had a similar issue with OpenCV image stitching. I've used create method to create stitcher instance and provided 5 images in vertical order to stitch method, but I've received insufficient memory error.
Panorama was successfully created after setting:
setWaveCorrection(false)
This solution will not be applicable if you need wave correction.
This may be related to the sequence of the stitching, I split a big picture into 3*3, and firstly I stitch them row by row and there is no problem, when I stitch them column by column, there is the problem same as you.