分享一段H264视频和AAC音频的RTP封包代码
1. H264视频的RTP封包
[c-sharp] view plaincopy
- static int h264_parse(Track *tr, uint8_t *data, size_t len)
- {
- h264_priv *priv = tr->private_data;
- // double nal_time; // see page 9 and 7.4.1.2
- size_t nalsize = 0, index = 0;
- uint8_t *p, *q;
- if (priv->is_avc) {
- while (1) {
- unsigned int i;
- if(index >= len) break;
- //get the nal size
- nalsize = 0;
- for(i = 0; i < priv->nal_length_size; i++)
- nalsize = (nalsize << 8) | data[index++];
- if(nalsize <= 1 || nalsize > len) {
- if(nalsize == 1) {
- index++;
- continue;
- } else {
- fnc_log(FNC_LOG_VERBOSE, "[h264] AVC: nal size %d", nalsize);
- break;
- }
- }
- if (DEFAULT_MTU >= nalsize) {
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- data + index, nalsize);
- fnc_log(FNC_LOG_VERBOSE, "[h264] single NAL");
- } else {
- // single NAL, to be fragmented, FU-A;
- frag_fu_a(data + index, nalsize, DEFAULT_MTU, tr);
- }
- index += nalsize;
- }
- } else {
- //seek to the first startcode
- for (p = data; p<data + len - 3; p++) {
- if (p[0] == 0 && p[1] == 0 && p[2] == 1) {
- break;
- }
- }
- if (p >= data + len) return ERR_PARSE;
- while (1) {
- //seek to the next startcode [0 0 1]
- for (q = p; q<data+len-3;q++) {
- if (q[0] == 0 && q[1] == 0 && q[2] == 1) {
- break;
- }
- }
- if (q >= data + len) break;
- if (DEFAULT_MTU >= q - p) {
- fnc_log(FNC_LOG_VERBOSE, "[h264] Sending NAL %d",p[0]&0x1f);
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- p, q - p);
- fnc_log(FNC_LOG_VERBOSE, "[h264] single NAL");
- } else {
- //FU-A
- fnc_log(FNC_LOG_VERBOSE, "[h264] frags");
- frag_fu_a(p, q - p, DEFAULT_MTU, tr);
- }
- p = q;
- }
- // last NAL
- fnc_log(FNC_LOG_VERBOSE, "[h264] last NAL %d",p[0]&0x1f);
- if (DEFAULT_MTU >= len - (p - data)) {
- fnc_log(FNC_LOG_VERBOSE, "[h264] no frags");
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- p, len - (p - data));
- } else {
- //FU-A
- fnc_log(FNC_LOG_VERBOSE, "[h264] frags");
- frag_fu_a(p, len - (p - data), DEFAULT_MTU, tr);
- }
- }
- fnc_log(FNC_LOG_VERBOSE, "[h264] Frame completed");
- return ERR_NOERROR;
- }
- static int h264_parse(Track *tr, uint8_t *data, size_t len)
- {
- h264_priv *priv = tr->private_data;
- // double nal_time; // see page 9 and 7.4.1.2
- size_t nalsize = 0, index = 0;
- uint8_t *p, *q;
- if (priv->is_avc) {
- while (1) {
- unsigned int i;
- if(index >= len) break;
- //get the nal size
- nalsize = 0;
- for(i = 0; i < priv->nal_length_size; i++)
- nalsize = (nalsize << 8) | data[index++];
- if(nalsize <= 1 || nalsize > len) {
- if(nalsize == 1) {
- index++;
- continue;
- } else {
- fnc_log(FNC_LOG_VERBOSE, "[h264] AVC: nal size %d", nalsize);
- break;
- }
- }
- if (DEFAULT_MTU >= nalsize) {
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- data + index, nalsize);
- fnc_log(FNC_LOG_VERBOSE, "[h264] single NAL");
- } else {
- // single NAL, to be fragmented, FU-A;
- frag_fu_a(data + index, nalsize, DEFAULT_MTU, tr);
- }
- index += nalsize;
- }
- } else {
- //seek to the first startcode
- for (p = data; p<data + len - 3; p++) {
- if (p[0] == 0 && p[1] == 0 && p[2] == 1) {
- break;
- }
- }
- if (p >= data + len) return ERR_PARSE;
- while (1) {
- //seek to the next startcode [0 0 1]
- for (q = p; q<data+len-3;q++) {
- if (q[0] == 0 && q[1] == 0 && q[2] == 1) {
- break;
- }
- }
- if (q >= data + len) break;
- if (DEFAULT_MTU >= q - p) {
- fnc_log(FNC_LOG_VERBOSE, "[h264] Sending NAL %d",p[0]&0x1f);
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- p, q - p);
- fnc_log(FNC_LOG_VERBOSE, "[h264] single NAL");
- } else {
- //FU-A
- fnc_log(FNC_LOG_VERBOSE, "[h264] frags");
- frag_fu_a(p, q - p, DEFAULT_MTU, tr);
- }
- p = q;
- }
- // last NAL
- fnc_log(FNC_LOG_VERBOSE, "[h264] last NAL %d",p[0]&0x1f);
- if (DEFAULT_MTU >= len - (p - data)) {
- fnc_log(FNC_LOG_VERBOSE, "[h264] no frags");
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- p, len - (p - data));
- } else {
- //FU-A
- fnc_log(FNC_LOG_VERBOSE, "[h264] frags");
- frag_fu_a(p, len - (p - data), DEFAULT_MTU, tr);
- }
- }
- fnc_log(FNC_LOG_VERBOSE, "[h264] Frame completed");
- return ERR_NOERROR;
- }
2. AAC的RTP封包
[c-sharp] view plaincopy
- static int aac_parse(Track *tr, uint8_t *data, size_t len)
- {
- //XXX handle the last packet on EOF
- int off = 0;
- uint32_t payload = DEFAULT_MTU - AU_HEADER_SIZE;
- uint8_t *packet = g_malloc0(DEFAULT_MTU);
- if(!packet) return ERR_ALLOC;
- // trim away extradata
- // data += AAC_EXTRA;
- // len -= AAC_EXTRA;
- packet[0] = 0x00;
- packet[1] = 0x10;
- packet[2] = (len & 0x1fe0) >> 5;
- packet[3] = (len & 0x1f) << 3;
- if (len > payload) {
- while (len > payload) {
- memcpy(packet + AU_HEADER_SIZE, data + off, payload);
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 0,
- packet, DEFAULT_MTU);
- len -= payload;
- off += payload;
- }
- }
- memcpy(packet + AU_HEADER_SIZE, data + off, len);
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- packet, len + AU_HEADER_SIZE);
- g_free(packet);
- return ERR_NOERROR;
- }
- static int aac_parse(Track *tr, uint8_t *data, size_t len)
- {
- //XXX handle the last packet on EOF
- int off = 0;
- uint32_t payload = DEFAULT_MTU - AU_HEADER_SIZE;
- uint8_t *packet = g_malloc0(DEFAULT_MTU);
- if(!packet) return ERR_ALLOC;
- // trim away extradata
- // data += AAC_EXTRA;
- // len -= AAC_EXTRA;
- packet[0] = 0x00;
- packet[1] = 0x10;
- packet[2] = (len & 0x1fe0) >> 5;
- packet[3] = (len & 0x1f) << 3;
- if (len > payload) {
- while (len > payload) {
- memcpy(packet + AU_HEADER_SIZE, data + off, payload);
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 0,
- packet, DEFAULT_MTU);
- len -= payload;
- off += payload;
- }
- }
- memcpy(packet + AU_HEADER_SIZE, data + off, len);
- mparser_buffer_write(tr,
- tr->properties.pts,
- tr->properties.dts,
- tr->properties.frame_duration,
- 1,
- packet, len + AU_HEADER_SIZE);
- g_free(packet);
- return ERR_NOERROR;
- }
上面的变量 AU_HEADER_SIZE=4
/* au header
+---------------------------------------+
| AU-size |
+---------------------------------------+
| AU-Index / AU-Index-delta |
+---------------------------------------+
| CTS-flag |
+---------------------------------------+
| CTS-delta |
+---------------------------------------+
| DTS-flag |
+---------------------------------------+
| DTS-delta |
+---------------------------------------+
| RAP-flag |
+---------------------------------------+
| Stream-state |
+---------------------------------------+
*/