diff options
| -rw-r--r-- | include/asterisk/translate.h | 18 | ||||
| -rw-r--r-- | main/translate.c | 42 |
2 files changed, 58 insertions, 2 deletions
diff --git a/include/asterisk/translate.h b/include/asterisk/translate.h index 07c0ae1c2..a03f54ef2 100644 --- a/include/asterisk/translate.h +++ b/include/asterisk/translate.h @@ -205,12 +205,26 @@ struct ast_frame *ast_translate(struct ast_trans_pvt *tr, struct ast_frame *f, i /*! * \brief Returns the number of steps required to convert from 'src' to 'dest'. - * \param dest Destination format - * \param src Source format + * \param dest destination format + * \param src source format * \return the number of translation steps required, or -1 if no path is available */ unsigned int ast_translate_path_steps(unsigned int dest, unsigned int src); +/*! + * \brief Mask off unavailable formats from a format bitmask + * \param dest possible destination formats + * \param src source formats + * \return the destination formats that are available in the source or translatable + * + * The result will include all formats from 'dest' that are either present + * in 'src' or translatable from a format present in 'src'. + * + * Note that only a single audio format and a single video format can be + * present in 'src', or the function will produce unexpected results. + */ +unsigned int ast_translate_available_formats(unsigned int dest, unsigned int src); + #if defined(__cplusplus) || defined(c_plusplus) } #endif diff --git a/main/translate.c b/main/translate.c index 77feabbac..f51822f3f 100644 --- a/main/translate.c +++ b/main/translate.c @@ -777,3 +777,45 @@ unsigned int ast_translate_path_steps(unsigned int dest, unsigned int src) return tr_matrix[src][dest].multistep + 1; } +unsigned int ast_translate_available_formats(unsigned int dest, unsigned int src) +{ + unsigned int res = dest; + unsigned int x; + unsigned int src_audio = powerof(src & AST_FORMAT_AUDIO_MASK); + unsigned int src_video = powerof(src & AST_FORMAT_VIDEO_MASK); + + for (x = 1; x < AST_FORMAT_MAX_AUDIO; x <<= 1) { + /* if this is not a desired format, nothing to do */ + if (!dest & x) + continue; + + /* if the source is supplying this format, then + we can leave it in the result */ + if (src & x) + continue; + + /* if we don't have a translation path from the src + to this format, remove it from the result */ + if (!tr_matrix[src_audio][powerof(x)].step) + res &= ~x; + } + + /* roll over into video formats */ + for (; x < AST_FORMAT_MAX_VIDEO; x <<= 1) { + /* if this is not a desired format, nothing to do */ + if (!dest & x) + continue; + + /* if the source is supplying this format, then + we can leave it in the result */ + if (src & x) + continue; + + /* if we don't have a translation path from the src + to this format, remove it from the result */ + if (!tr_matrix[src_video][powerof(x)].step) + res &= ~x; + } + + return res; +} |