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int out_w, /* Dimensions of output frame */</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int out_h,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int color_model,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
unsigned char **row_pointers,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int track);</span><br>
<br>
It lets you take a rectangular area from the file and writes it into
the buffer at a specified location. If input size and output size are
different, the image will be scaled. Finally, there is a legacy
version, which will only work for BC_RGB888:<br>
<br>
<span style="font-family: monospace;">int
quicktime_decode_video(quicktime_t *file,</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
unsigned char **row_pointers,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int track);</span><br>
<h4><a name="3.6_Video_seeking"></a>3.6 Video seeking</h4>
There are different approaches depending on your timing method.<br>
<br>
<span style="font-family: monospace;">lqt_seek_video(quicktime_t *
file, int track, </span><span style="font-family: monospace;">int64_t
time);</span><br style="font-family: monospace;">
<br>
seeks to the specified time given in timescale tics. Since the
timestamp of the next frame might be slightly different from<br>
the time you seeked to, use <span style="font-family: monospace;">lqt_frame_time
</span>to get the timestamp of the next frame. If you trust the
framerate and just count frames, you can use:<br>
<br>
<span style="font-family: monospace;">int
quicktime_set_video_position(quicktime_t *file, int64_t frame, int
track);</span><br>
<h4><a name="3.7_Global_information"></a>3.7 Global information</h4>
These are for information only. They play no role in the decoding
process. To find out, if the file is an AVI, use<br>
<br>
<span style="font-family: monospace;">int lqt_is_avi(quicktime_t *file);<br>
<br>
</span>Then, you can get the metadata as strings:<br>
<br>
<span style="font-family: monospace;">char*
quicktime_get_copyright(quicktime_t *file);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">char*
quicktime_get_name(quicktime_t *file);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">char*
quicktime_get_info(quicktime_t *file);</span><br>
<span style="font-family: monospace;">char * lqt_get_album(quicktime_t
* file);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">char * lqt_get_artist(quicktime_t
* file);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">char * lqt_get_genre(quicktime_t
* file);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">char * lqt_get_track(quicktime_t
* file);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">char *
lqt_get_comment(quicktime_t *file);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">char * lqt_get_author(quicktime_t
*file);</span><br>
<br>
Treat the return values as if they were const. No, libquicktime isn't
really const friendly ;-(<br>
<h3><a name="4._Writing_Quicktime_files"></a>4. Writing Quicktime files</h3>
<h4><a name="4.1_Setting_metadata"></a>4.1 Setting metadata</h4>
First, you might want to insert some information strings into your
file. Do this with:<br>
<br>
<span style="font-family: monospace;">void
quicktime_set_copyright(quicktime_t *file, char *string);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">void
quicktime_set_name(quicktime_t *file, char *string);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">void
quicktime_set_info(quicktime_t *file, char *string);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">void lqt_set_album(quicktime_t
*file, char *string);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">void lqt_set_artist(quicktime_t
*file, char *string);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">void lqt_set_genre(quicktime_t
*file, char *string);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">void lqt_set_track(quicktime_t
*file, char *string);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">void lqt_set_comment(quicktime_t
*file, char *string);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">void lqt_set_author(quicktime_t
*file, char *string);</span><span style="font-weight: bold;"><br>
</span>
<h4><a name="4.2_Setting_up_tracks"></a>4.2 Setting up tracks</h4>
To add an audio track, call:<br>
<br>
<span style="font-family: monospace;">int
lqt_add_audio_track(quicktime_t *file,</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp; &nbsp; &nbsp; &nbsp;
&nbsp; &nbsp; &nbsp;&nbsp;
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; int channels, long
sample_rate, int bits, lqt_codec_info_t * info);</span><br>
<br>
The bits argument is only relevant for the twos and sowt codecs. It
should be set to 16 by default. To add a video track, use:<br>
<br>
<span style="font-family: monospace;">int
lqt_add_video_track(quicktime_t *file,</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int frame_w, int frame_h,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int frame_duration, int timescale,</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
lqt_codec_info_t * info);</span><br>
<br>
The <span style="font-family: monospace;">frame_duration</span> should
is only important, if you use
<span style="font-family: monospace;">quicktime_encode_video</span>
(see below).<br>
<br>
<h4><a name="4.3_Setting_codec_parameters"></a>4.3 Setting codec
parameters</h4>
To set a parameter of audio and video codecs, call<br>
<br>
<span style="font-family: monospace;">void
lqt_set_audio_parameter(quicktime_t *file,int stream, char *key,void
*value);</span><br style="font-family: monospace;">
<span style="font-family: monospace;">void
lqt_set_video_parameter(quicktime_t *file,int stream, char *key,void
*value);</span><br>
<br>
value must be of type <span style="font-family: monospace;">char*</span>
for string parameters and <span style="font-family: monospace;">int*</span>
for integer parameters. See <a href="#6._Codec_registry_interface">Codec
registry interface</a> for methods to find out the encoding parameters.<br>
<h4><a name="4.4_Making_an_AVI"></a>4.4 Making an AVI</h4>
After you configured all codecs, you can tell the library to make an
AVI instead of a Quicktime file. It's done with:<br>
<br>
<span style="font-family: monospace;">void
quicktime_set_avi(quicktime_t *file, 1);</span><br
 style="font-family: monospace;">
<br>
Please note, that not all codecs are supported with AVI files. Some are
only supported in AVIs. See <a href="#6._Codec_registry_interface">Codec
registry interface</a> for more informtation about this.<br>
<h4><a name="4.5_Encoding_audio"></a>4.5 Encoding audio</h4>
To encode a buffer full of samples, use<br>
<br>
<span style="font-family: monospace;">int
lqt_encode_audio_track(quicktime_t *file,</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int16_t **channels_i,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
float **channels_f,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
long samples,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int track);</span><br style="font-family: monospace;">
<br>
Either channels_i or channels_f must be NULL.<br>
<h4><a name="4.6_Encoding_video"></a>4.6 Encoding video</h4>
Before you encode the first frame, you must decide which colormodel you
use (see <a href="#5._Colormodels">Colormodels</a>). You tell the
library about the colormodel with:<br>
<br>
<span style="font-family: monospace;">void lqt_set_cmodel(quicktime_t
*file, int track, int colormodel);</span><br>
<br>
Then, if you will use a planar format, and your memory had padded
scanlines, tell the byte offsets between the scanlines of the luminance
and chrominance planes:<br>
<br>
<span style="font-family: monospace;">void lqt_set_row_span(quicktime_t
*file, int track, int row_span);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">void
lqt_set_row_span_uv(quicktime_t *file, int track, int row_span_uv);</span><br
 style="font-family: monospace;">
<br>
Finally, if you source has individual tinestamps for all frames, call<br>
<br>
<span style="font-family: monospace;">int lqt_encode_video(quicktime_t
*file,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
unsigned char **row_pointers,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int track, int64_t time);</span><br style="font-family: monospace;">
<br>
The timestamp is given in timescale tics. <span
 style="font-family: monospace;">row_pointers</span> contains the
scanlines for packet formats and the planes <br>
for planar formats. If you have a constant frame duration and passed it
to <span style="font-family: monospace;">lqt_add_video_track</span>,
you might also use:<br>
<br>
<span style="font-family: monospace;">int
quicktime_encode_video(quicktime_t *file,</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
unsigned char **row_pointers,</span><br style="font-family: monospace;">
<span style="font-family: monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
int track);<br>
</span>
<h4><a name="4.7_Making_streamable_Quicktime"></a>4.7 Making streamable
Quicktime</h4>
By default, libquicktime will put the header (the moov atom) at the end
of the file. This means, that it won't be playable from a non-seekable
source (i.e. a http connection). To reorder the file to have the header
at the start, call:<br>
<br>
<span style="font-family: monospace;">int
quicktime_make_streamable(char *in_path, char *out_path);<br>
<br>
</span>This function must be called after you closed the file with <span
 style="font-family: monospace;">quicktime_close</span>. Note that you
need twice the disk space for this function.<span
 style="font-family: monospace;"><br>
</span>
<h3><a name="5._Colormodels"></a>5. Colormodels</h3>
The supported colormodels are defined in colormodels.h. Libquicktime
adds another value <span style="font-family: monospace;">LQT_COLORMODEL_NONE</span>,
which specifies an uninitialized or unknown colormodel. Informations
about the supported colormodels can be obtained with:<br>
<br>
<span style="font-family: monospace;">const char *
lqt_colormodel_to_string(int colormodel);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">int
lqt_string_to_colormodel(const char * str);</span><br
 style="font-family: monospace;">
<span style="font-family: monospace;">int lqt_colormodel_is_planar(int
colormodel);</span><br style="font-family: monospace;">