转：MPlayer源代码分析

config.h // 各种本地配置宏定义头
version.h // 版本定义头 #define VERSION "1.0pre7try2-3.4.2"
mp_msg.h // 消息处理头
help_mp.h // 根据配置自动生成的帮助头 #include "help/help_mpen.h"
cfg-mplayer-def.h // Mplayer 运行时的选项缺省值头文件 char*
default_config =  
sub_reader.h // 拥有格式自动发现功能的字幕(subtitle)阅读器
libvo/video_out.h // 该文件包含 libvo 视频输出的公共函数、变量
libvo/font_load.h // 有关字体装载的例程
libao2/audio_out.h // 音频输出驱动程序相关结构定义和全局数据
libmpcodecs/dec_audio.h // 音频解码
libmpcodecs/dec_video.h // 视频解码
libmpdemux/matroska.h // 多路解复用，媒体容器格式 matroska 处理头
libmpdemux/stream.h // 流处理
libmpdemux/demuxer.h // 多路解复用头文件
libmpdemux/stheader.h // 媒体流头处理
get_path.c // 路径获取头文件
spudec.h // SPU 子画面单元头，DVD 字幕流
edl.h // 剪辑控制清单
m_option.h // 选项类型处理头
m_config.h // 配置处理头文件

int main() {  
1) 变量声明，电影信息 movie info:  
2) 初始化，消息系统……  
play_next_file:  
3)播放文件 filename 的循环 goto play_next_file 开始  
main:  
4) 主处理 main  
5) 播放真正主循环 2010 ~3541 while (!eof)  
while (!eof) {  
5.1) 播放音频 PLAY AUDIO 2017 ~ 2064 decode_audio(sh_audio, ...);  
5.2) 播放视频 PLAY VIDEO, 2068 ~ 2300 decode_video(sh_video, ...);  
5.3) 处理暂停 PAUSE  
5.4) 处理 EDL  
5.5) 键盘事件处理, 搜索2400~3216 while (!brk_cmd &&  
(cmd=mp_input_get_cmd(0,0,0))!=NULL)  
5.6) 时间寻道(秒) if (seek_to_sec)  
5.7) 寻道 3243 ~ 3306, if (rel_seek_secs || abs_seek_pos)  
5.8) 处理 GUI  
5.9) 变更 Update OSD  
5.10) 找到字幕 find sub  
5.11) 处理 X11 窗口  
5.12) DVD 字幕 sub:  
}  
goto_next_file:  
6) 播放结束，转到下个文件 goto_next_file:  
}

mconfig = m_config_new();  
m_config_register_options(mconfig,mplayer_opts);  
// TODO : add something to let modules register their options
mp_input_register_options(mconfig);  
parse_cfgfiles(mconfig);

static MPContext *mpctx = &mpctx_s;  
// Not all functions in mplayer.c take the context as an argument yet
static MPContext mpctx_s = {  
.osd_function = OSD_PLAY,  
.begin_skip = MP_NOPTS_VALUE,  
.play_tree_step = 1,  
.global_sub_pos = -1,  
.set_of_sub_pos = -1,  
.file_format = DEMUXER_TYPE_UNKNOWN,  
.loop_times = -1,  
#ifdef HAS_DVBIN_SUPPORT
.last_dvb_step = 1,  
#endif
};

//真正统筹全局的结构
typedef struct MPContext {  
int osd_show_percentage;  
int osd_function;  
const ao_functions_t *audio_out;  
    play_tree_t *playtree;  
    play_tree_iter_t *playtree_iter;  
int eof;  
int play_tree_step;  
int loop_times;  

    stream_t *stream;  
    demuxer_t *demuxer;  
    sh_audio_t *sh_audio;  
    sh_video_t *sh_video;  
    demux_stream_t *d_audio;  
    demux_stream_t *d_video;  
    demux_stream_t *d_sub;  
    mixer_t mixer;  
const vo_functions_t *video_out;  
// Frames buffered in the vo ready to flip. Currently always 0 or 1.
// This is really a vo variable but currently there‘s no suitable vo
// struct.
int num_buffered_frames;  

// used to retry decoding after startup/seeking to compensate for codec delay
int startup_decode_retry;  
// how long until we need to display the "current" frame
float time_frame;  

// AV sync: the next frame should be shown when the audio out has this
// much (in seconds) buffered data left. Increased when more data is
// written to the ao, decreased when moving to the next frame.
// In the audio-only case used as a timer since the last seek
// by the audio CPU usage meter.
double delay;  

float begin_skip; ///< start time of the current skip while on edlout mode
// audio is muted if either EDL or user activates mute
short edl_muted; ///< Stores whether EDL is currently in muted mode.
short user_muted; ///< Stores whether user wanted muted mode.

int global_sub_size; // this encompasses all subtitle sources
int global_sub_pos; // this encompasses all subtitle sources
int set_of_sub_pos;  
int set_of_sub_size;  
int sub_counts[SUB_SOURCES];  
#ifdef CONFIG_ASS
// set_of_ass_tracks[i] contains subtitles from set_of_subtitles[i]
// parsed by libass or NULL if format unsupported
    ASS_Track* set_of_ass_tracks[MAX_SUBTITLE_FILES];  
#endif
    sub_data* set_of_subtitles[MAX_SUBTITLE_FILES];  

int file_format;  

#ifdef CONFIG_DVBIN
int last_dvb_step;  
int dvbin_reopen;  
#endif

int was_paused;  

#ifdef CONFIG_DVDNAV
struct mp_image *nav_smpi;   ///< last decoded dvdnav video image
    unsigned char *nav_buffer;   ///< last read dvdnav video frame
    unsigned char *nav_start;    ///< pointer to last read video buffer
int            nav_in_size;  ///< last read size
#endif
} MPContext;

mpctx->stream=open_stream(filename,0,&mpctx->file_format);  
fileformat 文件还是TV 流DEMUXER_TYPE_PLAYLIST 或DEMUXER_TYPE_UNKNOWN  
DEMUXER_TYPE_TV  
current_module记录状态vobsub open_stream handle_playlist dumpstream  
stream_reset(mpctx->stream);  
stream_seek(mpctx->stream,mpctx->stream->start_pos);  
f=fopen(stream_dump_name,”wb”); dump文件流  
stream->type==STREAMTYPE_DVD

mpctx->demuxer=demux_open(mpctx->stream,mpctx-  
>file_format,audio_id,video_id,dvdsub_id,filename);  
Demux过程  
demux_open  
get_demuxer_type_from_name  
……  
mpctx->d_audio=mpctx->demuxer->audio;  
mpctx->d_video=mpctx->demuxer->video;  
mpctx->d_sub=mpctx->demuxer->sub;  
mpctx->sh_audio=mpctx->d_audio->sh;  
mpctx->sh_video=mpctx->d_video->sh;

/*======================== PLAY VIDEO ============================*/
vo_pts=mpctx->sh_video->timer*90000.0;  
vo_fps=mpctx->sh_video->fps;  
if (!mpctx->num_buffered_frames) {  
double frame_time = update_video(&blit_frame);  
mp_dbg(MSGT_AVSYNC,MSGL_DBG2,”*** ftime=%5.3f ***\n”,frame_time);  
if (mpctx->sh_video->vf_inited < 0) {  
mp_msg(MSGT_CPLAYER,MSGL_FATAL, MSGTR_NotInitializeVOPorVO);  
mpctx->eof = 1; goto goto_next_file;  
}  
if (frame_time < 0)  
mpctx->eof = 1;  
else {  
// might return with !eof && !blit_frame if !correct_pts
mpctx->num_buffered_frames += blit_frame;  
time_frame += frame_time / playback_speed; // for nosound
}  
}

typedef struct vd_functions_s  
{  
vd_info_t *info;  
int (*init)(sh_video_t *sh);  
void (*uninit)(sh_video_t *sh);  
int (*control)(sh_video_t *sh,int cmd,void* arg, …);  
mp_image_t* (*decode)(sh_video_t *sh,void* data,int len,int flags);  
} vd_functions_t;

typedef struct mp_image_s {  
unsigned short flags;  
unsigned char type;  
unsigned char bpp; // bits/pixel. NOT depth! for RGB it will be n*8
unsigned int imgfmt;  
int width,height; // stored dimensions
int x,y,w,h; // visible dimensions
unsigned char* planes[MP_MAX_PLANES];  
int stride[MP_MAX_PLANES];  
char * qscale;  
int qstride;  
int pict_type; // 0->unknown, 1->I, 2->P, 3->B
int fields;  
int qscale_type; // 0->mpeg1/4/h263, 1->mpeg2
int num_planes;  
/* these are only used by planar formats Y,U(Cb),V(Cr) */
int chroma_width;  
int chroma_height;  
int chroma_x_shift; // horizontal
int chroma_y_shift; // vertical
/* for private use by filter or vo driver (to store buffer id or dmpi) */
void* priv;  
} mp_image_t;