Generalize the C-language Opus interface.
Switch to explicit channel mappings (RFC 7845) when creating
multi-stream Opus en/de-coders. The responsibility of setting up the
channel mappings will shift from WebRTC to the WebRTC user.
See https://webrtc-review.googlesource.com/c/src/+/121764 for the
current vision. See also the first child CL
https://webrtc-review.googlesource.com/c/src/+/129768
that sets up the Decoder to use this code.
Bug: webrtc:8649
Change-Id: I55959a293d54bb4c982eff68ec107c5ef8666c5c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/129767
Commit-Queue: Alex Loiko <aleloi@webrtc.org>
Reviewed-by: Oskar Sundbom <ossu@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27452}diff --git a/modules/audio_coding/codecs/opus/opus_interface.h b/modules/audio_coding/codecs/opus/opus_interface.h
index 0e97734..04eaba9 100644
--- a/modules/audio_coding/codecs/opus/opus_interface.h
+++ b/modules/audio_coding/codecs/opus/opus_interface.h
@@ -27,10 +27,10 @@
/****************************************************************************
* WebRtcOpus_EncoderCreate(...)
*
- * This function create an Opus encoder.
+ * This function creates an Opus encoder that encodes mono or stereo.
*
* Input:
- * - channels : number of channels.
+ * - channels : number of channels; 1 or 2.
* - application : 0 - VOIP applications.
* Favor speech intelligibility.
* 1 - Audio applications.
@@ -47,6 +47,36 @@
size_t channels,
int32_t application);
+/****************************************************************************
+ * WebRtcOpus_MultistreamEncoderCreate(...)
+ *
+ * This function creates an Opus encoder with any supported channel count.
+ *
+ * Input:
+ * - channels : number of channels.
+ * - application : 0 - VOIP applications.
+ * Favor speech intelligibility.
+ * 1 - Audio applications.
+ * Favor faithfulness to the original input.
+ * - coupled_streams : number of coupled streams, as described in
+ * RFC 7845.
+ * - channel_mapping : the channel mapping; pointer to array of
+ * `channel` bytes, as described in RFC 7845.
+ *
+ * Output:
+ * - inst : a pointer to Encoder context that is created
+ * if success.
+ *
+ * Return value : 0 - Success
+ * -1 - Error
+ */
+int16_t WebRtcOpus_MultistreamEncoderCreate(
+ OpusEncInst** inst,
+ size_t channels,
+ int32_t application,
+ size_t coupled_streams,
+ const unsigned char* channel_mapping);
+
int16_t WebRtcOpus_EncoderFree(OpusEncInst* inst);
/****************************************************************************
@@ -295,6 +325,32 @@
int16_t WebRtcOpus_SetForceChannels(OpusEncInst* inst, size_t num_channels);
int16_t WebRtcOpus_DecoderCreate(OpusDecInst** inst, size_t channels);
+
+/****************************************************************************
+ * WebRtcOpus_MultistreamDecoderCreate(...)
+ *
+ * This function creates an Opus decoder with any supported channel count.
+ *
+ * Input:
+ * - channels : number of channels.
+ * - coupled_streams : number of coupled streams, as described in
+ * RFC 7845.
+ * - channel_mapping : the channel mapping; pointer to array of
+ * `channel` bytes, as described in RFC 7845.
+ *
+ * Output:
+ * - inst : a pointer to a Decoder context that is created
+ * if success.
+ *
+ * Return value : 0 - Success
+ * -1 - Error
+ */
+int16_t WebRtcOpus_MultistreamDecoderCreate(
+ OpusDecInst** inst,
+ size_t channels,
+ size_t coupled_streams,
+ const unsigned char* channel_mapping);
+
int16_t WebRtcOpus_DecoderFree(OpusDecInst* inst);
/****************************************************************************