path: root/tinyDAV/src/codecs/h264/tdav_codec_h264_rtp.c

/*
* Copyright (C) 2010-2011 Mamadou Diop.
*
* Contact: Mamadou Diop <diopmamadou(at)doubango.org>
*	
* This file is part of Open Source Doubango Framework.
*
* DOUBANGO is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*	
* DOUBANGO is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*	
* You should have received a copy of the GNU General Public License
* along with DOUBANGO.
*
*/

/**@file tdav_codec_h264_rtp.c
 * @brief H.264 payloader/depayloder as per RFC 3984
 *
 * @author Mamadou Diop <diopmamadou(at)doubango.org>
 *
 */
#include "tinydav/codecs/h264/tdav_codec_h264_rtp.h"

#include "tinydav/codecs/h264/tdav_codec_h264_common.h"

#include "tinymedia/tmedia_codec.h"

#include "tsk_string.h"
#include "tsk_debug.h"

#include "tsk_memory.h"
#include <string.h> /* strlen() */
#include <stdlib.h> /* strtol() */

/*
*	ITU H.264 - http://www.itu.int/rec/T-REC-H.264-200903-S/en
*/

uint8_t H264_START_CODE_PREFIX[4] = { 0x00, 0x00, 0x00, 0x01 };

#define H264_NAL_UNIT_TYPE_HEADER_SIZE		1
#define H264_F_UNIT_TYPE_HEADER_SIZE		1
#define H264_FUA_HEADER_SIZE				2
#define H264_FUB_HEADER_SIZE				4
#define H264_NAL_AGG_MAX_SIZE			65535

static int tdav_codec_h264_get_fua_pay(const uint8_t* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size, tsk_bool_t* append_scp, tsk_bool_t* end_of_unit);
static int tdav_codec_h264_get_nalunit_pay(const uint8_t* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size);

// profile_level_id MUST be a "null-terminated" string
int tdav_codec_h264_parse_profile(const char* profile_level_id, profile_idc_t *p_idc, profile_iop_t *p_iop, level_idc_t *l_idc)
{
	uint32_t value;

	if(tsk_strlen(profile_level_id) != 6){
		TSK_DEBUG_ERROR("I say [%s] is an invalid profile-level-id", profile_level_id);
		return -1;
	}

	value = strtol(profile_level_id, tsk_null, 16);
	
	/* profile-idc */
	if(p_idc){
		switch((value >> 16)){
			case profile_idc_baseline:
				*p_idc = profile_idc_baseline;
				break;
			case profile_idc_extended:
				*p_idc = profile_idc_extended;
				break;
			case profile_idc_main:
				*p_idc = profile_idc_main;
				break;
			case profile_idc_high:
				*p_idc = profile_idc_high;
				break;
			default:
				*p_idc = profile_idc_none;
				break;
		}
	}
	
	/* profile-iop */
	if(p_iop){
		p_iop->constraint_set0_flag = ((value >> 8) & 0x80)>>7;
		p_iop->constraint_set1_flag = ((value >> 8) & 0x40)>>6;
		p_iop->constraint_set2_flag = ((value >> 8) & 0x20)>>5;
		p_iop->reserved_zero_5bits = ((value >> 8) & 0x1F);
	}

	/* level-idc */
	if(l_idc){
		switch((value & 0xFF)){
			case level_idc_1_0:
				*l_idc = level_idc_1_0;
				break;
			case level_idc_1_b:
				*l_idc = level_idc_1_b;
				break;
			case level_idc_1_1:
				*l_idc = level_idc_1_1;
				break;
			case level_idc_1_2:
				*l_idc = level_idc_1_2;
				break;
			case level_idc_1_3:
				*l_idc = level_idc_1_3;
				break;
			case level_idc_2_0:
				*l_idc = level_idc_2_0;
				break;
			case level_idc_2_1:
				*l_idc = level_idc_2_1;
				break;
			case level_idc_2_2:
				*l_idc = level_idc_2_2;
				break;
			case level_idc_3_0:
				*l_idc = level_idc_3_0;
				break;
			case level_idc_3_1:
				*l_idc = level_idc_3_1;
				break;
			case level_idc_3_2:
				*l_idc = level_idc_3_2;
				break;
			case level_idc_4_0:
				*l_idc = level_idc_4_0;
				break;
			case level_idc_4_1:
				*l_idc = level_idc_4_1;
				break;
			case level_idc_4_2:
				*l_idc = level_idc_4_2;
				break;
			case level_idc_5_0:
				*l_idc = level_idc_5_0;
				break;
			case level_idc_5_1:
				*l_idc = level_idc_5_1;
				break;
			case level_idc_5_2:
				*l_idc = level_idc_5_2;
				break;
			default:
				*l_idc = level_idc_none;
				break;
		}
	}

	return 0;
}

int tdav_codec_h264_get_pay(const void* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size, tsk_bool_t* append_scp, tsk_bool_t* end_of_unit)
{
	const uint8_t* pdata = (const uint8_t*)in_data;
	uint8_t nal_type;
	if (!in_data || !in_size || !out_data || !out_size || !append_scp || !end_of_unit) {
		TSK_DEBUG_ERROR("Invalid parameter");
		return -1;
	}

	*out_data = tsk_null;
	*out_size = 0;

	/* 5.3. NAL Unit Octet Usage
	  +---------------+
      |0|1|2|3|4|5|6|7|
      +-+-+-+-+-+-+-+-+
      |F|NRI|  Type   |
      +---------------+
	*/
	switch ((nal_type = (pdata[0] & 0x1F))) {
		case undefined_0:
		case undefined_30:
		case undefined_31:
		case stap_a:
		case stap_b:
		case mtap16:
		case mtap24:
		case fu_b:
			break;
		case fu_a:
			return tdav_codec_h264_get_fua_pay(pdata, in_size, out_data, out_size, append_scp, end_of_unit);
		default: /* NAL unit (1-23) */
			*append_scp = tsk_true; //(nal_type != 7 && nal_type != 8); // SPS or PPS
			*end_of_unit = tsk_true;
			return tdav_codec_h264_get_nalunit_pay(pdata, in_size, out_data, out_size);
	}

	TSK_DEBUG_WARN("%d not supported as valid NAL Unit type", (*pdata & 0x1F));
	return -1;
}


static int tdav_codec_h264_get_fua_pay(const uint8_t* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size, tsk_bool_t* append_scp, tsk_bool_t* end_of_unit)
{
	if (in_size <=H264_FUA_HEADER_SIZE) {
		TSK_DEBUG_ERROR("Too short");
		return -1;
	}
	/* RFC 3984 - 5.8. Fragmentation Units (FUs)

		 0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | FU indicator  |   FU header   |                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
      |                                                               |
      |                         FU payload                            |
      |                                                               |
      |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                               :...OPTIONAL RTP padding        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

	  The FU indicator octet has the following format:

      +---------------+
      |0|1|2|3|4|5|6|7|
      +-+-+-+-+-+-+-+-+
      |F|NRI|  Type   |
      +---------------+

	  The FU header has the following format:

      +---------------+
      |0|1|2|3|4|5|6|7|
      +-+-+-+-+-+-+-+-+
      |S|E|R|  Type   |
      +---------------+
	*/

    if (((in_data[1] & 0x80) /*S*/)) {
        /* discard "FU indicator" */
        *out_data = (in_data + H264_NAL_UNIT_TYPE_HEADER_SIZE);
        *out_size = (in_size - H264_NAL_UNIT_TYPE_HEADER_SIZE);
        
        // Do need to append Start Code Prefix ?
        /* S: 1 bit
         When set to one, the Start bit indicates the start of a fragmented
         NAL unit.  When the following FU payload is not the start of a
         fragmented NAL unit payload, the Start bit is set to zero.*/
        *append_scp = tsk_true;
        
        // F, NRI and Type
        *((uint8_t*)*out_data) = (in_data[0] & 0xe0) /* F,NRI from "FU indicator"*/ | (in_data[1] & 0x1f) /* type from "FU header" */;
    }
    else {
        *append_scp = tsk_false;
        *out_data = (in_data + H264_FUA_HEADER_SIZE);
        *out_size = (in_size - H264_FUA_HEADER_SIZE);
    }
	/*
	 E:     1 bit
          When set to one, the End bit indicates the end of a fragmented
          NAL unit, i.e., the last byte of the payload is also the last
          byte of the fragmented NAL unit.  When the following FU
          payload is not the last fragment of a fragmented NAL unit, the
          End bit is set to zero.
	  */
	*end_of_unit = (((in_data[1] & 0x40) /*E*/)) ? tsk_true : tsk_false;

	return 0;
}

static int tdav_codec_h264_get_nalunit_pay(const uint8_t* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size)
{

/*	5.6. Single NAL Unit Packet
	
	 0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |F|NRI|  type   |                                               |
      +-+-+-+-+-+-+-+-+                                               |
      |                                                               |
      |               Bytes 2..n of a Single NAL unit                 |
      |                                                               |
      |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                               :...OPTIONAL RTP padding        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/

	*out_data = in_data;
	*out_size =  in_size;

	return 0;
}

void tdav_codec_h264_rtp_encap(struct tdav_codec_h264_common_s* self, const uint8_t* pdata, tsk_size_t size)
{
	static const tsk_size_t size_of_scp = sizeof(H264_START_CODE_PREFIX); /* we know it's equal to 4 .. */
	register tsk_size_t i;
	tsk_size_t last_scp, prev_scp;
	tsk_size_t _size;

	if (!pdata || size < size_of_scp) {
		return;
	}

	if (pdata[0] == 0 && pdata[1] == 0) {
		if (pdata[2] == 1) {
			pdata += 3, size -= 3;
		}
		else if (pdata[2] == 0 && pdata[3] == 1) {
			pdata += 4, size -= 4;
		}
	}

	_size = (size - size_of_scp);
	last_scp = 0, prev_scp = 0;
	for (i = size_of_scp; i<_size; i++) {
		if (pdata[i] == 0 && pdata[i+1] == 0 && (pdata[i+2] == 1 || (pdata[i+2] == 0 && pdata[i+3] == 1))) {  /* Find Start Code Prefix */
			prev_scp = last_scp;
			if ((i - last_scp) >= H264_RTP_PAYLOAD_SIZE || 1) {
				tdav_codec_h264_rtp_callback(self, pdata + prev_scp,
					(i - prev_scp), (prev_scp == size));
			}
			last_scp = i;
			i += (pdata[i+2] == 1) ? 3 : 4;
		}
	}

	if (last_scp < (int32_t)size) {
			tdav_codec_h264_rtp_callback(self, pdata + last_scp,
				(size - last_scp), tsk_true);
	}
}

void tdav_codec_h264_rtp_callback(struct tdav_codec_h264_common_s *self, const void *data, tsk_size_t size, tsk_bool_t marker)
{
	uint8_t* pdata = (uint8_t*)data;

	//TSK_DEBUG_INFO("%x %x %x %x -- %u", pdata[0], pdata[1], pdata[2], pdata[3], size);

	if (size>4 && pdata[0] == H264_START_CODE_PREFIX[0] && pdata[1] == H264_START_CODE_PREFIX[1]) {
		if(pdata[2] == H264_START_CODE_PREFIX[3]){
			pdata += 3, size -= 3;
		}
		else if (pdata[2] == H264_START_CODE_PREFIX[2] && pdata[3] == H264_START_CODE_PREFIX[3]) {
			pdata += 4, size -= 4;
		}
	}
	
	//TSK_DEBUG_INFO("==> SCP %2x %2x %2x %2x", pdata[0], pdata[1], pdata[2], pdata[3]);

	if (self->pack_mode_local == Single_NAL_Unit_Mode || size < H264_RTP_PAYLOAD_SIZE) {
		if (self->pack_mode_local == Single_NAL_Unit_Mode && size > H264_RTP_PAYLOAD_SIZE) {
			TSK_DEBUG_WARN("pack_mode=Single_NAL_Unit_Mode but size(%d) > H264_RTP_PAYLOAD_SIZE(%d). Did you forget to set \"avctx->rtp_payload_size\"?", size, H264_RTP_PAYLOAD_SIZE);
		}
		// Can be packet in a Single Nal Unit
		// Send data over the network
		if (TMEDIA_CODEC_VIDEO(self)->out.callback) {
			TMEDIA_CODEC_VIDEO(self)->out.result.buffer.ptr = pdata;
			TMEDIA_CODEC_VIDEO(self)->out.result.buffer.size = size;
			TMEDIA_CODEC_VIDEO(self)->out.result.duration =  (uint32_t)((1./(double)TMEDIA_CODEC_VIDEO(self)->out.fps) * TMEDIA_CODEC(self)->plugin->rate);
			TMEDIA_CODEC_VIDEO(self)->out.result.last_chunck = marker;
			TMEDIA_CODEC_VIDEO(self)->out.callback(&TMEDIA_CODEC_VIDEO(self)->out.result);
		}
	}
	else if (size > H264_NAL_UNIT_TYPE_HEADER_SIZE) {
		/* Should be Fragmented as FUA */
		uint8_t fua_hdr[H264_FUA_HEADER_SIZE]; /* "FU indicator" and "FU header" - 2bytes */
		fua_hdr[0] = pdata[0] & 0x60/* NRI */, fua_hdr[0] |= fu_a;
		fua_hdr[1] = 0x80/* S=1,E=0,R=0 */, fua_hdr[1] |= pdata[0] & 0x1f; /* type */
		// discard header
		pdata += H264_NAL_UNIT_TYPE_HEADER_SIZE;
		size -= H264_NAL_UNIT_TYPE_HEADER_SIZE;

		while(size) {
			tsk_size_t packet_size = TSK_MIN(H264_RTP_PAYLOAD_SIZE, size);

			if (self->rtp.size < (packet_size + H264_FUA_HEADER_SIZE)){
				if(!(self->rtp.ptr = (uint8_t*)tsk_realloc(self->rtp.ptr, (packet_size + H264_FUA_HEADER_SIZE)))){
					TSK_DEBUG_ERROR("Failed to allocate new buffer");
					return;
				}
				self->rtp.size = (packet_size + H264_FUA_HEADER_SIZE);
			}
			// set E bit
			if((size - packet_size) == 0){
				// Last packet
				fua_hdr[1] |= 0x40;
			}
			// copy FUA header
			memcpy(self->rtp.ptr, fua_hdr, H264_FUA_HEADER_SIZE);
			// reset "S" bit
			fua_hdr[1] &= 0x7F;
			// copy data
			memcpy((self->rtp.ptr + H264_FUA_HEADER_SIZE), pdata, packet_size);
			pdata += packet_size;
			size -= packet_size;

			// send data
			if(TMEDIA_CODEC_VIDEO(self)->out.callback){
				TMEDIA_CODEC_VIDEO(self)->out.result.buffer.ptr = self->rtp.ptr;
				TMEDIA_CODEC_VIDEO(self)->out.result.buffer.size = (packet_size + H264_FUA_HEADER_SIZE);
				TMEDIA_CODEC_VIDEO(self)->out.result.duration =  (uint32_t)((1./(double)TMEDIA_CODEC_VIDEO(self)->out.fps) * TMEDIA_CODEC(self)->plugin->rate);
				TMEDIA_CODEC_VIDEO(self)->out.result.last_chunck = (size == 0);
				TMEDIA_CODEC_VIDEO(self)->out.callback(&TMEDIA_CODEC_VIDEO(self)->out.result);
			}
		}
	}
}