static GstFlowReturn gst_a52dec_handle_frame (GstAudioDecoder * bdec, GstBuffer * buffer) { GstA52Dec *a52dec; gint channels, i; gboolean need_reneg = FALSE; gint chans; gint length = 0, flags, sample_rate, bit_rate; GstMapInfo map; GstFlowReturn result = GST_FLOW_OK; GstBuffer *outbuf; const gint num_blocks = 6; a52dec = GST_A52DEC (bdec); /* no fancy draining */ if (G_UNLIKELY (!buffer)) return GST_FLOW_OK; /* parsed stuff already, so this should work out fine */ gst_buffer_map (buffer, &map, GST_MAP_READ); g_assert (map.size >= 7); /* re-obtain some sync header info, * should be same as during _parse and could also be cached there, * but anyway ... */ bit_rate = a52dec->bit_rate; sample_rate = a52dec->sample_rate; flags = 0; length = a52_syncinfo (map.data, &flags, &sample_rate, &bit_rate); g_assert (length == map.size); /* update stream information, renegotiate or re-streaminfo if needed */ need_reneg = FALSE; if (a52dec->sample_rate != sample_rate) { GST_DEBUG_OBJECT (a52dec, "sample rate changed"); need_reneg = TRUE; a52dec->sample_rate = sample_rate; } if (flags) { if (a52dec->stream_channels != (flags & (A52_CHANNEL_MASK | A52_LFE))) { GST_DEBUG_OBJECT (a52dec, "stream channel flags changed, marking update"); a52dec->flag_update = TRUE; } a52dec->stream_channels = flags & (A52_CHANNEL_MASK | A52_LFE); } if (bit_rate != a52dec->bit_rate) { a52dec->bit_rate = bit_rate; gst_a52dec_update_streaminfo (a52dec); } /* If we haven't had an explicit number of channels chosen through properties * at this point, choose what to downmix to now, based on what the peer will * accept - this allows a52dec to do downmixing in preference to a * downstream element such as audioconvert. */ if (a52dec->request_channels != A52_CHANNEL) { flags = a52dec->request_channels; } else if (a52dec->flag_update) { GstCaps *caps; a52dec->flag_update = FALSE; caps = gst_pad_get_allowed_caps (GST_AUDIO_DECODER_SRC_PAD (a52dec)); if (caps && gst_caps_get_size (caps) > 0) { GstCaps *copy = gst_caps_copy_nth (caps, 0); GstStructure *structure = gst_caps_get_structure (copy, 0); gint orig_channels = flags ? gst_a52dec_channels (flags, NULL) : 6; gint fixed_channels = 0; const int a52_channels[6] = { A52_MONO, A52_STEREO, A52_STEREO | A52_LFE, A52_2F2R, A52_2F2R | A52_LFE, A52_3F2R | A52_LFE, }; /* Prefer the original number of channels, but fixate to something * preferred (first in the caps) downstream if possible. */ gst_structure_fixate_field_nearest_int (structure, "channels", orig_channels); if (gst_structure_get_int (structure, "channels", &fixed_channels) && fixed_channels <= 6) { if (fixed_channels < orig_channels) flags = a52_channels[fixed_channels - 1]; } else { flags = a52_channels[5]; } gst_caps_unref (copy); } else if (flags) flags = a52dec->stream_channels; else flags = A52_3F2R | A52_LFE; if (caps) gst_caps_unref (caps); } else { flags = a52dec->using_channels; } /* process */ flags |= A52_ADJUST_LEVEL; a52dec->level = 1; if (a52_frame (a52dec->state, map.data, &flags, &a52dec->level, a52dec->bias)) { gst_buffer_unmap (buffer, &map); GST_AUDIO_DECODER_ERROR (a52dec, 1, STREAM, DECODE, (NULL), ("a52_frame error"), result); goto exit; } gst_buffer_unmap (buffer, &map); channels = flags & (A52_CHANNEL_MASK | A52_LFE); if (a52dec->using_channels != channels) { need_reneg = TRUE; a52dec->using_channels = channels; } /* negotiate if required */ if (need_reneg) { GST_DEBUG_OBJECT (a52dec, "a52dec reneg: sample_rate:%d stream_chans:%d using_chans:%d", a52dec->sample_rate, a52dec->stream_channels, a52dec->using_channels); if (!gst_a52dec_reneg (a52dec)) goto failed_negotiation; } if (a52dec->dynamic_range_compression == FALSE) { a52_dynrng (a52dec->state, NULL, NULL); } flags &= (A52_CHANNEL_MASK | A52_LFE); chans = gst_a52dec_channels (flags, NULL); if (!chans) goto invalid_flags; /* handle decoded data; * each frame has 6 blocks, one block is 256 samples, ea */ outbuf = gst_buffer_new_and_alloc (256 * chans * (SAMPLE_WIDTH / 8) * num_blocks); gst_buffer_map (outbuf, &map, GST_MAP_WRITE); { guint8 *ptr = map.data; for (i = 0; i < num_blocks; i++) { if (a52_block (a52dec->state)) { /* also marks discont */ GST_AUDIO_DECODER_ERROR (a52dec, 1, STREAM, DECODE, (NULL), ("error decoding block %d", i), result); if (result != GST_FLOW_OK) { gst_buffer_unmap (outbuf, &map); goto exit; } } else { gint n, c; gint *reorder_map = a52dec->channel_reorder_map; for (n = 0; n < 256; n++) { for (c = 0; c < chans; c++) { ((sample_t *) ptr)[n * chans + reorder_map[c]] = a52dec->samples[c * 256 + n]; } } } ptr += 256 * chans * (SAMPLE_WIDTH / 8); } } gst_buffer_unmap (outbuf, &map); result = gst_audio_decoder_finish_frame (bdec, outbuf, 1); exit: return result; /* ERRORS */ failed_negotiation: { GST_ELEMENT_ERROR (a52dec, CORE, NEGOTIATION, (NULL), (NULL)); return GST_FLOW_ERROR; } invalid_flags: { GST_ELEMENT_ERROR (GST_ELEMENT (a52dec), STREAM, DECODE, (NULL), ("Invalid channel flags: %d", flags)); return GST_FLOW_ERROR; } }
static GstFlowReturn gst_a52dec_handle_frame (GstA52Dec * a52dec, guint8 * data, guint length, gint flags, gint sample_rate, gint bit_rate) { gint channels, i; gboolean need_reneg = FALSE; /* update stream information, renegotiate or re-streaminfo if needed */ need_reneg = FALSE; if (a52dec->sample_rate != sample_rate) { need_reneg = TRUE; a52dec->sample_rate = sample_rate; } if (flags) { a52dec->stream_channels = flags & (A52_CHANNEL_MASK | A52_LFE); } if (bit_rate != a52dec->bit_rate) { a52dec->bit_rate = bit_rate; gst_a52dec_update_streaminfo (a52dec); } /* If we haven't had an explicit number of channels chosen through properties * at this point, choose what to downmix to now, based on what the peer will * accept - this allows a52dec to do downmixing in preference to a * downstream element such as audioconvert. */ if (a52dec->request_channels != A52_CHANNEL) { flags = a52dec->request_channels; } else if (a52dec->flag_update) { GstCaps *caps; a52dec->flag_update = FALSE; caps = gst_pad_get_allowed_caps (a52dec->srcpad); if (caps && gst_caps_get_size (caps) > 0) { GstCaps *copy = gst_caps_copy_nth (caps, 0); GstStructure *structure = gst_caps_get_structure (copy, 0); gint channels; const int a52_channels[6] = { A52_MONO, A52_STEREO, A52_STEREO | A52_LFE, A52_2F2R, A52_2F2R | A52_LFE, A52_3F2R | A52_LFE, }; /* Prefer the original number of channels, but fixate to something * preferred (first in the caps) downstream if possible. */ gst_structure_fixate_field_nearest_int (structure, "channels", flags ? gst_a52dec_channels (flags, NULL) : 6); gst_structure_get_int (structure, "channels", &channels); if (channels <= 6) flags = a52_channels[channels - 1]; else flags = a52_channels[5]; gst_caps_unref (copy); } else if (flags) flags = a52dec->stream_channels; else flags = A52_3F2R | A52_LFE; if (caps) gst_caps_unref (caps); } else { flags = a52dec->using_channels; } /* process */ flags |= A52_ADJUST_LEVEL; a52dec->level = 1; if (a52_frame (a52dec->state, data, &flags, &a52dec->level, a52dec->bias)) { GST_WARNING ("a52_frame error"); a52dec->discont = TRUE; return GST_FLOW_OK; } channels = flags & (A52_CHANNEL_MASK | A52_LFE); if (a52dec->using_channels != channels) { need_reneg = TRUE; a52dec->using_channels = channels; } /* negotiate if required */ if (need_reneg) { GST_DEBUG ("a52dec reneg: sample_rate:%d stream_chans:%d using_chans:%d", a52dec->sample_rate, a52dec->stream_channels, a52dec->using_channels); if (!gst_a52dec_reneg (a52dec, a52dec->srcpad)) { GST_ELEMENT_ERROR (a52dec, CORE, NEGOTIATION, (NULL), (NULL)); return GST_FLOW_ERROR; } } if (a52dec->dynamic_range_compression == FALSE) { a52_dynrng (a52dec->state, NULL, NULL); } /* each frame consists of 6 blocks */ for (i = 0; i < 6; i++) { if (a52_block (a52dec->state)) { /* ignore errors but mark a discont */ GST_WARNING ("a52_block error %d", i); a52dec->discont = TRUE; } else { GstFlowReturn ret; /* push on */ ret = gst_a52dec_push (a52dec, a52dec->srcpad, a52dec->using_channels, a52dec->samples, a52dec->time); if (ret != GST_FLOW_OK) return ret; } a52dec->time += 256 * GST_SECOND / a52dec->sample_rate; } return GST_FLOW_OK; }