# 3gpapp syntax

3gpapp is installed in the C:\nms\bin\ directory in Windows or the /opt/nms/bin/ directory in UNIX.

3gpapp uses the following syntax:

3gpapp command command-option [file1] [file2] [file3]

where:

Argument | Description
command | The command to execute. Valid values are described in the command table.
command-option | The command option associated with a command. Valid values are described in the command-option table.
file1, file2, file3 | Full names (including extensions) of the files being acted on by a 3gpapp command. For more information, see the individual command descriptions.

The following table describes the 3gpapp commands and lists their associated options:

Command | Description | Associated command options
-c | Create a 3GP file (file1) from an existing audio file (file2), video file (file3), or both. Audio and video files can be either in NMS packetized or raw format. | -b: Buffer size -H: Header check -I: Interleaving depth -g: Hint tracks -s: Maximum size -t: Maximum time -v: Verbosity level -w: Creation mode -y: Sync points -z: Skew correction
-d | Display detailed information from a 3GP file. | -v: Verbosity level
-e | Extract audio data, video data, or both from a 3gp file (file1), and create raw or NMS packetized files (file2). The file extension for file2 is a codec-dependent extension. | -b: Buffer size -f: Format of extracted media data -m: NMS packet max transfer unit -Q: Hint tracks -R: H.263 packetization format -v: Verbosity level -Y: Seek
-h | Display a help screen and exit. | NA
-i | Display general information from an existing 3GP file (file1). | -v: Verbosity level
-r | Rebuild a 3GP file. This process creates a new 3GP file (file2) with media data extracted from an existing 3GP file (file1). | -b: Buffer size -c: Creation mode -H: Header check -I: Interleaving depth -q: Hint tracks -s: Size -t: Maximum time -v: Verbosity level -y: Sync points -z: Skew correction

The following table describes the 3gpapp command options:

Option | Description | Use with these commands
-bsize | Buffer size to use, in bytes. Default is 0 (use the whole stream). | -c, -e, and -r
-fformat | Format of media data. Valid values are: 0 (default): NMS packetized 1: Raw | -e Raw format cannot be used with the partial buffer option (-b with a non-zero value).
-H | NMS header check when building the 3GP file. | -c and -r
-Idepth | Interleaving depth of streams, in milliseconds. The default is 1000. | -c and -r
-mn | NMS packet max transfer unit (mtu) size, in bytes. The default is 1432. | -e
-p | Read SDP information from a text file and insert it into a 3GP file. | -c and -r
-P | Extract SDP information from a 3GP file and write it to a text file. | -e
-q | Add RTP hint tracks to the 3GP file. | -c and -r
-Q | Use RTP hint tracks to packetize media data. | -e
-R | Changes the packetization mode for H.263 media to RFC 2190, when specified. The default packetization mode is RFC 2429. | -e
-ssize | Maximum size of the 3GP file, in bytes. | -c and -r
-ttime | Maximum file duration, in milliseconds, for all included media streams in the 3GP file. A value of 0 (zero) indicates that the time is not limited. | -c and -r
-wmode | Method of creating the 3GP file. Valid values are: 1: Write directly to the 3GP file. 2 (default): Write to temporary files. | -c and -r
-vlevel | Verbosity level for standard output. Valid values are: 0: None 1: Complete information, including debug, warning and error information 2: Debug information 4: Warning information 8: Error information | All
-y | Create sync points when building the 3GP file. | -c and -r
-Yseektime | Seek to a specific time in milliseconds. | -e
-zskewtime | Enable skew correction by insertion and removal of audio frames. | -c and -r