int theora_decode_header(theora_info *_ci,theora_comment *_cc,ogg_packet *_op){
th_api_wrapper *api;
th_info info;
int ret;
api=(th_api_wrapper *)_ci->codec_setup;
/*Allocate an API wrapper struct on demand, since it will not also include a
theora_info struct like the ones that are used in a theora_state struct.*/
if(api==NULL){
_ci->codec_setup=_ogg_calloc(1,sizeof(*api));
if(_ci->codec_setup==NULL)return OC_FAULT;
api=(th_api_wrapper *)_ci->codec_setup;
api->clear=(oc_setup_clear_func)th_dec_api_clear;
}
/*Convert from the theora_info struct instead of saving our own th_info
struct between calls.
The user might be doing something "clever" with the header packets if they
are not using an Ogg encapsulation, and we don't want to break this.*/
oc_theora_info2th_info(&info,_ci);
/*We rely on the fact that theora_comment and th_comment structures are
actually identical.
Take care not to change this fact unless you change the code here as
well!*/
ret=th_decode_headerin(&info,(th_comment *)_cc,&api->setup,_op);
/*We also rely on the fact that the error return code values are the same,
and that the implementations of these two functions return the same set of
them.
Note that theora_decode_header() really can return OC_NOTFORMAT, even
though it is not currently documented to do so.*/
if(ret<0)return ret;
th_info2theora_info(_ci,&info);
return 0;
}
int theora_decode_init(theora_state *_td,theora_info *_ci){
th_api_info *apiinfo;
th_api_wrapper *api;
th_info info;
api=(th_api_wrapper *)_ci->codec_setup;
/*Allocate our own combined API wrapper/theora_info struct.
We put them both in one malloc'd block so that when the API wrapper is
freed, the info struct goes with it.
This avoids having to figure out whether or not we need to free the info
struct in either theora_info_clear() or theora_clear().*/
apiinfo=(th_api_info *)_ogg_calloc(1,sizeof(*apiinfo));
/*Make our own copy of the info struct, since its lifetime should be
independent of the one we were passed in.*/
*&apiinfo->info=*_ci;
/*Convert the info struct now instead of saving the the one we decoded with
theora_decode_header(), since the user might have modified values (i.e.,
color space, aspect ratio, etc. can be specified from a higher level).
The user also might be doing something "clever" with the header packets if
they are not using an Ogg encapsulation.*/
oc_theora_info2th_info(&info,_ci);
/*Don't bother to copy the setup info; th_decode_alloc() makes its own copy
of the stuff it needs.*/
apiinfo->api.decode=th_decode_alloc(&info,api->setup);
if(apiinfo->api.decode==NULL){
_ogg_free(apiinfo);
return OC_EINVAL;
}
apiinfo->api.clear=(oc_setup_clear_func)th_dec_api_clear;
_td->internal_encode=NULL;
/*Provide entry points for ABI compatibility with old decoder shared libs.*/
_td->internal_decode=(void *)&OC_DEC_DISPATCH_VTBL;
_td->granulepos=0;
_td->i=&apiinfo->info;
_td->i->codec_setup=&apiinfo->api;
return 0;
}
int theora_encode_init(theora_state *_te,theora_info *_ci){
th_api_info *apiinfo;
th_info info;
ogg_uint32_t keyframe_frequency_force;
/*Allocate our own combined API wrapper/theora_info struct.
We put them both in one malloc'd block so that when the API wrapper is
freed, the info struct goes with it.
This avoids having to figure out whether or not we need to free the info
struct in either theora_info_clear() or theora_clear().*/
apiinfo=(th_api_info *)_ogg_malloc(sizeof(*apiinfo));
if(apiinfo==NULL)return TH_EFAULT;
/*Make our own copy of the info struct, since its lifetime should be
independent of the one we were passed in.*/
*&apiinfo->info=*_ci;
oc_theora_info2th_info(&info,_ci);
apiinfo->api.encode=th_encode_alloc(&info);
if(apiinfo->api.encode==NULL){
_ogg_free(apiinfo);
return OC_EINVAL;
}
apiinfo->api.clear=(oc_setup_clear_func)th_enc_api_clear;
/*Provide entry points for ABI compatibility with old decoder shared libs.*/
_te->internal_encode=(void *)&OC_ENC_DISPATCH_VTBL;
_te->internal_decode=NULL;
_te->granulepos=0;
_te->i=&apiinfo->info;
_te->i->codec_setup=&apiinfo->api;
/*Set the precise requested keyframe frequency.*/
keyframe_frequency_force=_ci->keyframe_auto_p?
_ci->keyframe_frequency_force:_ci->keyframe_frequency;
th_encode_ctl(apiinfo->api.encode,
TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE,
&keyframe_frequency_force,sizeof(keyframe_frequency_force));
/*TODO: Additional codec setup using the extra fields in theora_info.*/
return 0;
}
