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'''Etheora''' is a a simplified API to programming theora video encoding/decoding applications with ogg containers. It uses and  encapsulates libtheora + libogg API and structures, so users need to know very few  about video and data containers.
'''Etheora''' is a a simplified API for programming [[Theora]] video encoding/decoding applications with [[Ogg]] containers. It uses and  encapsulates libtheora + libogg API and structures, so users need to know very few  about video and data containers.
 
== Overview - Encoding ==


An encoding process is made by these steps:
An encoding process is made by these steps:
<nowiki>
/*a context declaration.*/
etheora_ctx *ec;


/*encoder configuration.*/
/* a context declaration. */
etheora_enc_configure(&ec, width, height, ETHEORA_ASPECT_NORMAL,
etheora_ctx ec;
fopen("output-video.ogg"), fopen("debug_info.txt"));


/*encoder start.*/
/* encoder configuration. */
etheora_enc_start(&ec);
etheora_enc_setup(&ec, width, height, ETHEORA_ASPECT_NORMAL,
fopen("output-video.ogv"), fopen("debug_info.txt"));


/*drawing next frame, by puting a r,g,b or y,u,v pixel in (i,j) coordinate*/
/* encoder start. */
etheora_enc_rgb_draw(&ec, i, j, r, g, b) (alternative: etheora_enc_yuv_draw()),
etheora_enc_start(&ec);


/*submiting frame to encoding.*/
/* drawing next frame, by puting a r,g,b or y,u,v pixel in (i,j) coordinate */
etheora_enc_nextframe(&ec);
etheora_enc_rgb_draw(&ec, i, j, r, g, b);
/* alternative: etheora_enc_yuv_draw()) */


/*submiting last frame to encoding by finishing the process.*/
/* submiting frame to encoding. */
etheora_enc_finish(&ec);
etheora_enc_nextframe(&ec);


/* submiting last frame to encoding by finishing the process. */
etheora_enc_finish(&ec);
The functions _yuv_ and _rgb_ works transparently with OC_PF_420, OC_PF_422 and OC_PF_PF_444, having the libtheora version used support for them or not.
== Overview - Decoding ==


The decoding process is quite similar.
The decoding process is quite similar.
/*a context declaration.*/
etheora_ctx *ec;


/*decoder configuration.*/
/* a context declaration. */
etheora_dec_configure(&ec, fopen("input-video.ogg"), fopen("debug_info.txt"));
etheora_ctx ec;


/*decoder start.*/
/* decoder configuration. */
etheora_dec_start(&ec);
etheora_dec_setup(&ec, fopen("input-video.ogv"), fopen("debug_info.txt"));  


/*reading video data.*/
/* decoder start. */
etheora_get_width(&ec);
etheora_dec_start(&ec);  
etheora_get_heigth(&ec);
etheora_get_fps_numerator(&ec);
etheora_get_fps_denominator(&ec);
etheora_get_aspect_numerator(&ec);
etheora_get_aspect_denominator(&ec);


/*getting next frame by decoding it.*/
/* reading video data. */
etheora_dec_nextframe(&ec);
etheora_get_width(&ec);
etheora_get_heigth(&ec);
etheora_get_fps_numerator(&ec);
etheora_get_fps_denominator(&ec);
etheora_get_aspect_numerator(&ec);
etheora_get_aspect_denominator(&ec);


/*getting frame data, by reading a r,g,b or y,u,v pixel in (i,j) coordinate*/
/* getting next frame by decoding it. */
etheora_dec_rgb_read(&ec, i, j, &r, &g, &b) (alternative:
etheora_dec_nextframe(&ec);
etheora_dec_yuv_read()),


/* finishing the process.*/
/* getting frame data, by reading a r,g,b or y,u,v pixel in (i,j) coordinate*/
etheora_dec_finish(&ec);
etheora_dec_rgb_read(&ec, i, j, &r, &g, &b)
/* alternative: etheora_dec_yuv_read()) */


the functions _yuv_ and _rgb_ works transparently with OC_PF_420,
/* finishing the process. */
OC_PF_422 and OC_PF_PF_444, having the libtheora version used support
etheora_dec_finish(&ec);
for them or not.
 
</nowiki>
The functions _yuv_ and _rgb_ works transparently with OC_PF_420, OC_PF_422 and OC_PF_PF_444, having the libtheora version used support for them or not.
 
== Overview - Going Further ==


Etheora is documented here:
Etheora is documented here:
http://svn.xiph.org/branches/etheora-0.1/doc/etheora_documentation.pdf
http://svn.xiph.org/branches/etheora-0.1.1/doc/etheora_documentation.pdf


Etheora code is here:
Etheora code is here:
http://svn.xiph.org/branches/etheora-0.1/src/
http://svn.xiph.org/branches/etheora-0.1.1/src/
 
Etheora very simple examples are found here:
http://svn.xiph.org/branches/etheora-0.1.1/examples/
 
Etheora still doesn't have audio/speech support. (Although it can get video data from videos with audio). And uses internally the old libtheora API (ie, not the theora-exp). FIXME: The theora-exp API is what's used now on libtheora 1.0.  Please use that API instead.
 
== TODO ==
 
* Vorbis support
* Speex support
* Skeleton support


Etheora examples are here:
== See also ==
http://svn.xiph.org/branches/etheora-0.1/examples/
{{Theora}}


Etheora still doesn't have audio/speech support. (Although it can get video data from videos with audio). And uses internally the old libtheora API (ie, not the theora-exp).
[[Category:Theora]]

Latest revision as of 15:02, 6 July 2008

Etheora is a a simplified API for programming Theora video encoding/decoding applications with Ogg containers. It uses and encapsulates libtheora + libogg API and structures, so users need to know very few about video and data containers.

Overview - Encoding

An encoding process is made by these steps:

/* a context declaration. */
etheora_ctx ec;
/* encoder configuration. */
etheora_enc_setup(&ec, width, height, ETHEORA_ASPECT_NORMAL,
fopen("output-video.ogv"), fopen("debug_info.txt"));
/* encoder start. */
etheora_enc_start(&ec);
/* drawing next frame, by puting a r,g,b or y,u,v pixel in (i,j) coordinate */
etheora_enc_rgb_draw(&ec, i, j, r, g, b);
/* alternative: etheora_enc_yuv_draw()) */
/* submiting frame to encoding. */
etheora_enc_nextframe(&ec);
/* submiting last frame to encoding by finishing the process. */
etheora_enc_finish(&ec);

The functions _yuv_ and _rgb_ works transparently with OC_PF_420, OC_PF_422 and OC_PF_PF_444, having the libtheora version used support for them or not.

Overview - Decoding

The decoding process is quite similar.

/* a context declaration. */
etheora_ctx ec;
/* decoder configuration. */
etheora_dec_setup(&ec, fopen("input-video.ogv"), fopen("debug_info.txt")); 
/* decoder start. */
etheora_dec_start(&ec); 
/* reading video data. */
etheora_get_width(&ec);
etheora_get_heigth(&ec);
etheora_get_fps_numerator(&ec);
etheora_get_fps_denominator(&ec);
etheora_get_aspect_numerator(&ec);
etheora_get_aspect_denominator(&ec);
/* getting next frame by decoding it. */
etheora_dec_nextframe(&ec); 
/* getting frame data, by reading a r,g,b or y,u,v pixel in (i,j) coordinate*/
etheora_dec_rgb_read(&ec, i, j, &r, &g, &b)
/* alternative: etheora_dec_yuv_read()) */
/* finishing the process. */
etheora_dec_finish(&ec);

The functions _yuv_ and _rgb_ works transparently with OC_PF_420, OC_PF_422 and OC_PF_PF_444, having the libtheora version used support for them or not.

Overview - Going Further

Etheora is documented here: http://svn.xiph.org/branches/etheora-0.1.1/doc/etheora_documentation.pdf

Etheora code is here: http://svn.xiph.org/branches/etheora-0.1.1/src/

Etheora very simple examples are found here: http://svn.xiph.org/branches/etheora-0.1.1/examples/

Etheora still doesn't have audio/speech support. (Although it can get video data from videos with audio). And uses internally the old libtheora API (ie, not the theora-exp). FIXME: The theora-exp API is what's used now on libtheora 1.0. Please use that API instead.

TODO

  • Vorbis support
  • Speex support
  • Skeleton support

See also