rm.c

pmpmodavc102_sub_src,psp下很好的播放器源码

//                av_log(NULL, AV_LOG_DEBUG, "%X %X\n", st->codec->codec_tag, MKTAG('R', 'V', '2', '0'));
                if (   st->codec->codec_tag != MKTAG('R', 'V', '1', '0')
                    && st->codec->codec_tag != MKTAG('R', 'V', '2', '0')
                    && st->codec->codec_tag != MKTAG('R', 'V', '3', '0')
                    && st->codec->codec_tag != MKTAG('R', 'V', '4', '0'))
                    goto fail1;
                st->codec->width = get_be16(pb);
                st->codec->height = get_be16(pb);
                st->codec->time_base.num= 1;
                fps= get_be16(pb);
                st->codec->codec_type = CODEC_TYPE_VIDEO;
                get_be32(pb);
                fps2= get_be16(pb);
                get_be16(pb);
                
                st->codec->extradata_size= codec_data_size - (url_ftell(pb) - codec_pos);
                st->codec->extradata= av_malloc(st->codec->extradata_size);
                get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
                
//                av_log(NULL, AV_LOG_DEBUG, "fps= %d fps2= %d\n", fps, fps2);
                st->codec->time_base.den = fps * st->codec->time_base.num;
                /* modification of h263 codec version (!) */
#ifdef WORDS_BIGENDIAN
                h263_hack_version = ((uint32_t*)st->codec->extradata)[1];
#else
                h263_hack_version = bswap_32(((uint32_t*)st->codec->extradata)[1]);
#endif
                st->codec->sub_id = h263_hack_version;
                switch((h263_hack_version>>28)){
                case 1: st->codec->codec_id = CODEC_ID_RV10; break;
                case 2: st->codec->codec_id = CODEC_ID_RV20; break;
                case 3: st->codec->codec_id = CODEC_ID_RV30; break;
                case 4: st->codec->codec_id = CODEC_ID_RV40; break;
                default: goto fail1;
                }
            }
skip:
            /* skip codec info */
            size = url_ftell(pb) - codec_pos;
            url_fskip(pb, codec_data_size - size);
            break;
        case MKTAG('D', 'A', 'T', 'A'):
            goto header_end;
        default:
            /* unknown tag: skip it */
            url_fskip(pb, tag_size - 10);
            break;
        }
    }
 header_end:
    rm->nb_packets = get_be32(pb); /* number of packets */
    if (!rm->nb_packets && (flags & 4))
        rm->nb_packets = 3600 * 25;
    get_be32(pb); /* next data header */
    return 0;

 fail:
    for(i=0;i<s->nb_streams;i++) {
        av_free(s->streams[i]);
    }
    return AVERROR_IO;
}

static int get_num(ByteIOContext *pb, int *len)
{
    int n, n1;

    n = get_be16(pb);
    (*len)-=2;
    if (n >= 0x4000) {
        return n - 0x4000;
    } else {
        n1 = get_be16(pb);
        (*len)-=2;
        return (n << 16) | n1;
    }
}

/* multiple of 20 bytes for ra144 (ugly) */
#define RAW_PACKET_SIZE 1000

static int sync(AVFormatContext *s, int64_t *timestamp, int *flags, int *stream_index, int64_t *pos){
    RMContext *rm = s->priv_data;
    ByteIOContext *pb = &s->pb;
    int len, num, res, i;
    AVStream *st;
    uint32_t state=0xFFFFFFFF;

    while(!url_feof(pb)){
        *pos= url_ftell(pb);
        if(rm->remaining_len > 0){
            num= rm->current_stream;
            len= rm->remaining_len;
            *timestamp = AV_NOPTS_VALUE;
            *flags= 0;
        }else{
            state= (state<<8) + get_byte(pb);
            
            if(state == MKBETAG('I', 'N', 'D', 'X')){
                len = get_be16(pb) - 6;
                if(len<0)
                    continue;
                goto skip;
            }
            
            if(state > (unsigned)0xFFFF || state < 12)
                continue;
            len=state;
            state= 0xFFFFFFFF;

            num = get_be16(pb);
            *timestamp = get_be32(pb);
            res= get_byte(pb); /* reserved */
            *flags = get_byte(pb); /* flags */

            
            len -= 12;
        }
        for(i=0;i<s->nb_streams;i++) {
            st = s->streams[i];
            if (num == st->id)
                break;
        }
        if (i == s->nb_streams) {
skip:
            /* skip packet if unknown number */
            url_fskip(pb, len);
            rm->remaining_len -= len;
            continue;
        }
        *stream_index= i;
        
        return len;
    }
    return -1;
}

static int rm_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    RMContext *rm = s->priv_data;
    ByteIOContext *pb = &s->pb;
    AVStream *st;
    int i, len, tmp, j;
    int64_t timestamp, pos;
    uint8_t *ptr;
    int flags;

    if (rm->old_format) {
        /* just read raw bytes */
        len = RAW_PACKET_SIZE;
        len= av_get_packet(pb, pkt, len);
        pkt->stream_index = 0;
        if (len <= 0) {
            return AVERROR_IO;
        }
        pkt->size = len;
        st = s->streams[0];
    } else {
        int seq=1;
resync:
        len=sync(s, &timestamp, &flags, &i, &pos);
        if(len<0)
            return AVERROR_IO;
        st = s->streams[i];

        if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
            int h, pic_num, len2, pos;

            h= get_byte(pb); len--;
            if(!(h & 0x40)){
                seq = get_byte(pb); len--;
            }

            if((h & 0xc0) == 0x40){
                len2= pos= 0;
            }else{
                len2 = get_num(pb, &len);
                pos = get_num(pb, &len);
            }
            /* picture number */
            pic_num= get_byte(pb); len--;
            rm->remaining_len= len;
            rm->current_stream= st->id;

//            av_log(NULL, AV_LOG_DEBUG, "%X len:%d pos:%d len2:%d pic_num:%d\n",h, len, pos, len2, pic_num);
            if(len2 && len2<len)
                len=len2;
            rm->remaining_len-= len;
        }

        if(  (st->discard >= AVDISCARD_NONKEY && !(flags&2))
           || st->discard >= AVDISCARD_ALL){
            url_fskip(pb, len);
            goto resync;
        }
        
        av_get_packet(pb, pkt, len);
        pkt->stream_index = i;

#if 0
        if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
            if(st->codec->codec_id == CODEC_ID_RV20){
                int seq= 128*(pkt->data[2]&0x7F) + (pkt->data[3]>>1);
                av_log(NULL, AV_LOG_DEBUG, "%d %Ld %d\n", timestamp, timestamp*512LL/25, seq);

                seq |= (timestamp&~0x3FFF);
                if(seq - timestamp >  0x2000) seq -= 0x4000;
                if(seq - timestamp < -0x2000) seq += 0x4000;
            }
        }
#endif
        pkt->pts= timestamp;
        if(flags&2){
            pkt->flags |= PKT_FLAG_KEY;
            if((seq&0x7F) == 1)
                av_add_index_entry(st, pos, timestamp, 0, AVINDEX_KEYFRAME);
        }
    }

    /* for AC3, needs to swap bytes */
    if (st->codec->codec_id == CODEC_ID_AC3) {
        ptr = pkt->data;
        for(j=0;j<len;j+=2) {
            tmp = ptr[0];
            ptr[0] = ptr[1];
            ptr[1] = tmp;
                ptr += 2;
        }
    }
    return 0;
}

static int rm_read_close(AVFormatContext *s)
{
    return 0;
}

static int rm_probe(AVProbeData *p)
{
    /* check file header */
    if (p->buf_size <= 32)
        return 0;
    if ((p->buf[0] == '.' && p->buf[1] == 'R' &&
         p->buf[2] == 'M' && p->buf[3] == 'F' &&
         p->buf[4] == 0 && p->buf[5] == 0) ||
        (p->buf[0] == '.' && p->buf[1] == 'r' &&
         p->buf[2] == 'a' && p->buf[3] == 0xfd))
        return AVPROBE_SCORE_MAX;
    else
        return 0;
}

static int64_t rm_read_dts(AVFormatContext *s, int stream_index, 
                               int64_t *ppos, int64_t pos_limit)
{
    RMContext *rm = s->priv_data;
    int64_t pos, dts;
    int stream_index2, flags, len, h;

    pos = *ppos;
    
    if(rm->old_format)
        return AV_NOPTS_VALUE;

    url_fseek(&s->pb, pos, SEEK_SET);
    rm->remaining_len=0;
    for(;;){
        int seq=1;
        AVStream *st;

        len=sync(s, &dts, &flags, &stream_index2, &pos);
        if(len<0)
            return AV_NOPTS_VALUE;

        st = s->streams[stream_index2];
        if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
            h= get_byte(&s->pb); len--;
            if(!(h & 0x40)){
                seq = get_byte(&s->pb); len--;
            }
        }
            
        if((flags&2) && (seq&0x7F) == 1){
//            av_log(s, AV_LOG_DEBUG, "%d %d-%d %Ld %d\n", flags, stream_index2, stream_index, dts, seq);
            av_add_index_entry(st, pos, dts, 0, AVINDEX_KEYFRAME);
            if(stream_index2 == stream_index)
                break;
        }

        url_fskip(&s->pb, len);
    }
    *ppos = pos;
    return dts;
}

static AVInputFormat rm_iformat = {
    "rm",
    "rm format",
    sizeof(RMContext),
    rm_probe,
    rm_read_header,
    rm_read_packet,
    rm_read_close,
    NULL,
    rm_read_dts,
};

#ifdef CONFIG_MUXERS
static AVOutputFormat rm_oformat = {
    "rm",
    "rm format",
    "application/vnd.rn-realmedia",
    "rm,ra",
    sizeof(RMContext),
    CODEC_ID_AC3,
    CODEC_ID_RV10,
    rm_write_header,
    rm_write_packet,
    rm_write_trailer,
};
#endif //CONFIG_MUXERS

int rm_init(void)
{
    av_register_input_format(&rm_iformat);
#ifdef CONFIG_MUXERS
    av_register_output_format(&rm_oformat);
#endif //CONFIG_MUXERS
    return 0;
}