new feature, if no video in all student and teacher,the output mp4 is also no video

@@ -34,13 +34,14 @@ int g_fps;
 
 #define ensure_no_zero(x, v) if(!x) x = v
 
-CAVTranscoder::CAVTranscoder(bool bOne2One, bool one2one_same_size, bool one2many_inflat, int width_teacher, int height_teacher, int width_student, int height_student, bool has_teacher, int max_audio,int keep_4_3) :
+CAVTranscoder::CAVTranscoder(bool bOne2One, bool one2one_same_size, bool one2many_inflat, int width_teacher, int height_teacher, int width_student, int height_student, bool has_teacher, int max_audio, int max_video, int keep_4_3) :
 _start_time(INT64_MAX),
 _all_processed(true),
 _nOutputWidth(320),
 _cur_out_v_ts(0),
 _cur_out_a_ts(0),
-_max_audio(1),
+_max_audio(max_audio),
+_max_video(max_video),
 _sws_ctx_w_h(NULL),
 _sws_ctx_h_w(NULL),
 _sws_ctx_h_h(NULL),
@@ -133,6 +134,8 @@ _one2one_same_size(one2one_same_size)
 		init_scale_context(&_sws_ctx_h_h, &_scaled_frame_h_h, _student_height, _student_height, _scaled_height, _scaled_height);
 	}
 	RGB2YUV(blank_r, blank_g, blank_b, &_blank_y, &_blank_u, &_blank_v);
+
+	_n_streams = max_video > 0 ? 2 : 1;
 }
 
 
@@ -182,7 +185,9 @@ double CAVTranscoder::transcode()
 	
 	_all_processed = decoders_got_frame.size() == 0;
 
-	mix_and_output_vframe(decoders_got_frame);
+	if (_max_video > 0) {
+		mix_and_output_vframe(decoders_got_frame);
+	}
 
 	_cur_v_time += g_vframe_duration;
 	
@@ -214,8 +219,9 @@ bool CAVTranscoder::all_processed()
 
 int CAVTranscoder::close()
 {
-	flush_encoder(0);
-	flush_encoder(1);
+	for (int i = 0; i < _n_streams; i++){
+		flush_encoder(i);
+	}
 	av_write_trailer(_ofmt_ctx);
 
 	free_scale_context(&_sws_ctx_w_h, &_scaled_frame_w_h);
@@ -238,7 +244,7 @@ int CAVTranscoder::close()
 	av_bitstream_filter_close(aacbsfc);
 #endif  
 	unsigned int i;
-	for (i = 0; i<2; i++)
+	for (i = 0; i< _n_streams; i++)
 	{
 		if (_ofmt_ctx && _ofmt_ctx->nb_streams > i && _ofmt_ctx->streams[i] && _ofmt_ctx->streams[i]->codec)
 			avcodec_close(_ofmt_ctx->streams[i]->codec);
@@ -267,7 +273,9 @@ int CAVTranscoder::open_output_file(const char *filename)
 		return AVERROR_UNKNOWN;
 	}
 
-	for (i = 0; i < 2; i++) {
+	
+
+	for (i = 0; i < _n_streams; i++) {
 		out_stream = avformat_new_stream(_ofmt_ctx, NULL);
 		if (!out_stream) {
 			av_log(NULL, AV_LOG_ERROR, "Failed allocating output stream\n");
@@ -279,7 +287,7 @@ int CAVTranscoder::open_output_file(const char *filename)
 		if (_ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
 			enc_ctx->flags |= CODEC_FLAG_GLOBAL_HEADER;
 
-		if (0 == i) {
+		if (1 == i) {
 			encoder = avcodec_find_encoder(AV_CODEC_ID_H264);
 			if (!encoder) {
 				av_log(NULL, AV_LOG_FATAL, "Necessary encoder not found\n");
@@ -449,7 +457,7 @@ int CAVTranscoder::open_output_file(const char *filename)
 		_cur_out_a_ts += 1024;
 
 		int got_frame = 0;
-		encode_write_frame(pDstFrame, 1, &got_frame);
+		encode_write_frame(pDstFrame, 0, &got_frame);
 
 		return 0;
 	}
@@ -598,7 +606,7 @@ int CAVTranscoder::open_output_file(const char *filename)
 
 		//send to encoder
 		int got_frame = 0;
-		encode_write_frame(pDstFrame, 0, &got_frame);
+		encode_write_frame(pDstFrame, 1, &got_frame);
 
 		return 0;
 	}
@@ -1100,7 +1108,7 @@ int CAVTranscoder::open_output_file(const char *filename)
 
 		//send to encoder
 		int got_frame = 0;
-		encode_write_frame(pDstFrame, 0, &got_frame);
+		encode_write_frame(pDstFrame, 1, &got_frame);
 
 		return 0;
 	}
@@ -1111,7 +1119,7 @@ int CAVTranscoder::encode_write_frame(AVFrame *filt_frame, unsigned int stream_i
 	AVPacket enc_pkt;
 
 	int(*enc_func)(AVCodecContext *, AVPacket *, const AVFrame *, int *) =
-		stream_index == 0 ? avcodec_encode_video2 : avcodec_encode_audio2;
+		stream_index == 1 ? avcodec_encode_video2 : avcodec_encode_audio2;
 
 	if (!got_frame)
 		got_frame = &got_frame_local;
@@ -1193,8 +1201,3 @@ int CAVTranscoder::free_scale_context(SwsContext ** ctx, AVFrame ** frame)
 	}
 	return 0;
 }
-
-void CAVTranscoder::set_max_audio(int max_audio)
-{
-	_max_audio = max_audio;
-}

@@ -5,7 +5,7 @@
 class CAVTranscoder
 {
 public:
-	CAVTranscoder(bool bOne2One, bool one2one_same_size, bool one2many_inflat, int width_teacher, int height_teacher, int student_width, int student_height, bool has_teacher, int max_audio, int keep_4_3= true);
+	CAVTranscoder(bool bOne2One, bool one2one_same_size, bool one2many_inflat, int width_teacher, int height_teacher, int student_width, int student_height, bool has_teacher, int max_audio, int max_video, int keep_4_3= true);
 	virtual ~CAVTranscoder();
 
 	int add(media_info & info);
@@ -45,6 +45,8 @@ private:
 
 	void * _a_frame_pool;
 	int _max_audio;
+	int _max_video;
+	int _n_streams;
 	int _scaled_width;
 	int	_scaled_height;
 	int _pip_width;
@@ -75,8 +77,6 @@ private:
 	int _src_height_student;
 
 	uint8_t _blank_y, _blank_u, _blank_v;
-public:
-	void set_max_audio(int max_audio);
 private:
 	int scale_fill_one2one_studentframe(AVFrame * pDstFrame, int y);
 	int fill_one2one_student_frame(AVFrame * pDstFrame, int y);

@@ -637,6 +637,8 @@ void add_media_info_with_end(media_info m)
 }
 
 list<media_info> audio_files;
+list<media_info> video_files;
+
 
 int count_audio_files(float mid)
 {
@@ -655,7 +657,25 @@ int count_audio_files(float mid)
 	return files;
 }
 
+int count_video_files(float mid)
+{
+	int files = 0;
+	list<media_info>::iterator it = video_files.begin();
+	for (; it != video_files.end(); it++){
+		if (it->start_time < mid){
+			if (it->end_time > mid) {
+				files++;
+			}
+		}
+		else {
+			break;
+		}
+	}
+	return files;
+}
+
 int max_audio = 1;
+int max_video = 0;
 int width = 0;
 int height = 0;
 int width_teacher = 0;
@@ -705,6 +725,9 @@ void add_media_infos()
 		if (it->m_type == mt_audio) {
 				audio_files.push_back(*it);
 		}
+		else if (it->m_type == mt_video) {
+			video_files.push_back(*it);
+		}
 	}
 
 	list<media_info> audio_type_files;
@@ -800,6 +823,38 @@ void add_media_infos()
 			}
 		}
 	}
+
+
+	list<media_info> video_type_files;
+
+	it = sorted_media_with_end.begin();
+	for (; it != sorted_media_with_end.end(); it++){
+		if (it->m_type == mt_video) {
+			video_type_files.push_back(*it);
+		}
+	}
+
+	it = video_type_files.begin();
+	if (it != video_type_files.end()) {
+		media_info last = *it;
+
+		for (it++; it != video_type_files.end(); it++) {
+			if (it->t_type == tt_end) {
+				if (last.t_type == tt_start) {
+					float mid = (it->type_time + last.type_time) / 2;
+					int files_with_mid = count_video_files(mid);
+					if (files_with_mid > max_video) {
+						max_video = files_with_mid;
+					}
+				}
+			}
+			else {
+				last = *it;
+			}
+		}
+	}
+
+
 }
 
 void unifiy_start_time()
@@ -1097,7 +1152,10 @@ int process_av_files(char * record_info, int piptype, bool one2one_same_size, in
 {
 	time_t start, end;
 	time(&start);
-	load_record_info(record_info);
+	if (load_record_info(record_info)){
+		printf("\nerror open record info file: %s", record_info);
+		return -1;
+	}
 
 	get_outinfo_file_name(record_info);
 
@@ -1139,8 +1197,7 @@ int process_av_files(char * record_info, int piptype, bool one2one_same_size, in
 		}
 	}
 
-	CAVTranscoder videoTranscoder(one2one, one2one_same_size, one_to_many_inflat, width_teacher, height_teacher, width_student, height_student, has_teacher, max_audio);
-	videoTranscoder.set_max_audio(max_audio);
+	CAVTranscoder videoTranscoder(one2one, one2one_same_size, one_to_many_inflat, width_teacher, height_teacher, width_student, height_student, has_teacher, max_audio, max_video);
 
 	int64_t cur_time = 0;
 	bool has_file = sorted_media.size()!=0;