asf-enc.c

arm平台下的H264编码和解码源代码

                cur_pos = url_ftell(pb);
                url_fseek(pb, es_pos, SEEK_SET);
                put_le32(pb, wavsize); /* wav header len */
                url_fseek(pb, cur_pos, SEEK_SET);
            }
        } else {
            put_le32(pb, enc->width);
            put_le32(pb, enc->height);
            put_byte(pb, 2); /* ??? */
            put_le16(pb, 40); /* size */

            /* BITMAPINFOHEADER header */
            put_bmp_header(pb, enc, codec_bmp_tags, 1);
        }
        end_header(pb, hpos);
    }

    /* media comments */

    hpos = put_header(pb, &codec_comment_header);
    put_guid(pb, &codec_comment1_header);
    put_le32(pb, s->nb_streams);
    for(n=0;n<s->nb_streams;n++) {
        AVCodec *p;

        enc = &s->streams[n]->codec;
        p = avcodec_find_encoder(enc->codec_id);

        put_le16(pb, asf->streams[n].num);
        put_str16(pb, p ? p->name : enc->codec_name);
        put_le16(pb, 0); /* no parameters */
        
        
        /* id */
        if (enc->codec_type == CODEC_TYPE_AUDIO) {
            put_le16(pb, 2);
            if(!enc->codec_tag)
                enc->codec_tag = codec_get_tag(codec_wav_tags, enc->codec_id);
            if(!enc->codec_tag)
                return -1;
            put_le16(pb, enc->codec_tag);
        } else {
            put_le16(pb, 4);
            if(!enc->codec_tag)
                enc->codec_tag = codec_get_tag(codec_bmp_tags, enc->codec_id);
            if(!enc->codec_tag)
                return -1;
            put_le32(pb, enc->codec_tag);
        }
    }
    end_header(pb, hpos);

    /* patch the header size fields */

    cur_pos = url_ftell(pb);
    header_size = cur_pos - header_offset;
    if (asf->is_streamed) {
        header_size += 8 + 30 + 50;

        url_fseek(pb, header_offset - 10 - 30, SEEK_SET);
        put_le16(pb, header_size);
        url_fseek(pb, header_offset - 2 - 30, SEEK_SET);
        put_le16(pb, header_size);

        header_size -= 8 + 30 + 50;
    }
    header_size += 24 + 6;
    url_fseek(pb, header_offset - 14, SEEK_SET);
    put_le64(pb, header_size);
    url_fseek(pb, cur_pos, SEEK_SET);

    /* movie chunk, followed by packets of packet_size */
    asf->data_offset = cur_pos;
    put_guid(pb, &data_header);
    put_le64(pb, data_chunk_size);
    put_guid(pb, &my_guid);
    put_le64(pb, asf->nb_packets); /* nb packets */
    put_byte(pb, 1); /* ??? */
    put_byte(pb, 1); /* ??? */
    return 0;
}

static int asf_write_header(AVFormatContext *s)
{
    ASFContext *asf = s->priv_data;

    av_set_pts_info(s, 32, 1, 1000); /* 32 bit pts in ms */

    asf->packet_size = PACKET_SIZE;
    asf->nb_packets = 0;

    if (asf_write_header1(s, 0, 50) < 0) {
        //av_free(asf);
        return -1;
    }

    put_flush_packet(&s->pb);

    asf->packet_nb_payloads = 0;
    asf->prev_packet_sent_time = 0;
    asf->packet_timestamp_start = -1;
    asf->packet_timestamp_end = -1;
    init_put_byte(&asf->pb, asf->packet_buf, asf->packet_size, 1,
                  NULL, NULL, NULL, NULL);

    return 0;
}

static int asf_write_stream_header(AVFormatContext *s)
{
    ASFContext *asf = s->priv_data;

    asf->is_streamed = 1;

    return asf_write_header(s);
}

static int put_payload_parsing_info(
                                AVFormatContext *s,
                                unsigned int    sendtime, 
                                unsigned int    duration,
                                int             nb_payloads, 
                                int             padsize
            )
{
    ASFContext *asf = s->priv_data;
    ByteIOContext *pb = &s->pb;
    int ppi_size, i;
    unsigned char *start_ppi_ptr = pb->buf_ptr;

    int iLengthTypeFlags = ASF_PPI_LENGTH_TYPE_FLAGS;
  
    put_byte(pb, ASF_PACKET_ERROR_CORRECTION_FLAGS);
    for (i = 0; i < ASF_PACKET_ERROR_CORRECTION_DATA_SIZE; i++){
        put_byte(pb, 0x0);
    }

    if (asf->multi_payloads_present)
        iLengthTypeFlags |= ASF_PPI_FLAG_MULTIPLE_PAYLOADS_PRESENT;

    if (padsize > 0) {
        if (padsize < 256)
            iLengthTypeFlags |= ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_BYTE;
        else
            iLengthTypeFlags |= ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_WORD;
    }
    put_byte(pb, iLengthTypeFlags);

    put_byte(pb, ASF_PPI_PROPERTY_FLAGS);

    if (iLengthTypeFlags & ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_WORD)
        put_le16(pb, padsize - 2);
    if (iLengthTypeFlags & ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_BYTE)
        put_byte(pb, padsize - 1);

    put_le32(pb, sendtime);
    put_le16(pb, duration);
    if (asf->multi_payloads_present)
        put_byte(pb, nb_payloads | ASF_PAYLOAD_FLAGS);

    ppi_size = pb->buf_ptr - start_ppi_ptr;

    return ppi_size;
}

static void flush_packet(AVFormatContext *s)
{
    ASFContext *asf = s->priv_data;
    int packet_hdr_size, packet_filled_size;

    if (asf->is_streamed) {
        put_chunk(s, 0x4424, asf->packet_size, 0);
    }

    packet_hdr_size = put_payload_parsing_info(
                            s,
                            asf->packet_timestamp_start,
                            asf->packet_timestamp_end - asf->packet_timestamp_start,
                            asf->packet_nb_payloads,
                            asf->packet_size_left
                        );

    packet_filled_size = PACKET_SIZE - packet_hdr_size - asf->packet_size_left;
    memset(asf->packet_buf + packet_filled_size, 0, asf->packet_size_left);

    put_buffer(&s->pb, asf->packet_buf, asf->packet_size - packet_hdr_size);

    put_flush_packet(&s->pb);
    asf->nb_packets++;
    asf->packet_nb_payloads = 0;
    asf->prev_packet_sent_time = asf->packet_timestamp_start;
    asf->packet_timestamp_start = -1;
    asf->packet_timestamp_end = -1;
    init_put_byte(&asf->pb, asf->packet_buf, asf->packet_size, 1,
                  NULL, NULL, NULL, NULL);
}

static void put_payload_header(
                                AVFormatContext *s,
                                ASFStream       *stream,
                                int             presentation_time,
                                int             m_obj_size,
                                int             m_obj_offset,
                                int             payload_len
            )
{
    ASFContext *asf = s->priv_data;
    ByteIOContext *pb = &asf->pb;
    int val;
    
    val = stream->num;
    if (s->streams[val - 1]->codec.coded_frame->key_frame)
        val |= ASF_PL_FLAG_KEY_FRAME;
    put_byte(pb, val);
        
    put_byte(pb, stream->seq);  //Media object number
    put_le32(pb, m_obj_offset); //Offset Into Media Object
         
    // Replicated Data shall be at least 8 bytes long.
    // The first 4 bytes of data shall contain the 
    // Size of the Media Object that the payload belongs to.
    // The next 4 bytes of data shall contain the 
    // Presentation Time for the media object that the payload belongs to.
    put_byte(pb, ASF_PAYLOAD_REPLICATED_DATA_LENGTH);

    put_le32(pb, m_obj_size);       //Replicated Data - Media Object Size
    put_le32(pb, presentation_time);//Replicated Data - Presentation Time
    
    if (asf->multi_payloads_present){
        put_le16(pb, payload_len);   //payload length
    }
}

static void put_frame(
                    AVFormatContext *s,
                    ASFStream       *stream,
		    int             timestamp,
                    const uint8_t   *buf,
		    int             m_obj_size
		)
{
    ASFContext *asf = s->priv_data;
    int m_obj_offset, payload_len, frag_len1;

    m_obj_offset = 0;
    while (m_obj_offset < m_obj_size) {
        payload_len = m_obj_size - m_obj_offset;
        if (asf->packet_timestamp_start == -1) {
            asf->multi_payloads_present = (payload_len < MULTI_PAYLOAD_CONSTANT);
            
            if (asf->multi_payloads_present){
                asf->packet_size_left = PACKET_SIZE; //For debug
                asf->packet_size_left = PACKET_SIZE - PACKET_HEADER_MIN_SIZE - 1;
                frag_len1 = MULTI_PAYLOAD_CONSTANT - 1;
            }
            else {
                asf->packet_size_left = PACKET_SIZE - PACKET_HEADER_MIN_SIZE;
                frag_len1 = SINGLE_PAYLOAD_DATA_LENGTH;
            }
            if (asf->prev_packet_sent_time > timestamp)
                asf->packet_timestamp_start = asf->prev_packet_sent_time;
            else
                asf->packet_timestamp_start = timestamp;
        }
        else {
            // multi payloads
            frag_len1 = asf->packet_size_left - PAYLOAD_HEADER_SIZE_MULTIPLE_PAYLOADS;

            if (asf->prev_packet_sent_time > timestamp)
                asf->packet_timestamp_start = asf->prev_packet_sent_time;
            else if (asf->packet_timestamp_start >= timestamp)
                asf->packet_timestamp_start = timestamp;
        }
        if (frag_len1 > 0) {
            if (payload_len > frag_len1)
                payload_len = frag_len1;
            else if (payload_len == (frag_len1 - 1))
                payload_len = frag_len1 - 2;  //additional byte need to put padding length
            
            put_payload_header(s, stream, timestamp+preroll_time, m_obj_size, m_obj_offset, payload_len);
            put_buffer(&asf->pb, buf, payload_len);

            if (asf->multi_payloads_present)
                asf->packet_size_left -= (payload_len + PAYLOAD_HEADER_SIZE_MULTIPLE_PAYLOADS);
            else
                asf->packet_size_left -= (payload_len + PAYLOAD_HEADER_SIZE_SINGLE_PAYLOAD);
            asf->packet_timestamp_end = timestamp;
            
            asf->packet_nb_payloads++;
        } else {
            payload_len = 0;
        }
        m_obj_offset += payload_len;
        buf += payload_len;

        if (!asf->multi_payloads_present)
            flush_packet(s);
        else if (asf->packet_size_left <= (PAYLOAD_HEADER_SIZE_MULTIPLE_PAYLOADS + 1))
            flush_packet(s);
    }
    stream->seq++;
}

static int asf_write_packet(AVFormatContext *s, int stream_index,
                            const uint8_t *buf, int size, int64_t timestamp)
{
    ASFContext *asf = s->priv_data;
    ASFStream *stream;
    int64_t duration;
    AVCodecContext *codec;

    codec = &s->streams[stream_index]->codec;
    stream = &asf->streams[stream_index];

    if (codec->codec_type == CODEC_TYPE_AUDIO) {
        duration = (codec->frame_number * codec->frame_size * int64_t_C(10000000)) /
            codec->sample_rate;
    } else {
        duration = av_rescale(codec->frame_number * codec->frame_rate_base, 10000000, codec->frame_rate);
    }
    if (duration > asf->duration)
        asf->duration = duration;

    put_frame(s, stream, timestamp, buf, size);
    return 0;
}

static int asf_write_trailer(AVFormatContext *s)
{
    ASFContext *asf = s->priv_data;
    int64_t file_size;

    /* flush the current packet */
    if (asf->pb.buf_ptr > asf->pb.buffer)
        flush_packet(s);

    if (asf->is_streamed) {
        put_chunk(s, 0x4524, 0, 0); /* end of stream */
    } else {
        /* rewrite an updated header */
        file_size = url_ftell(&s->pb);
        url_fseek(&s->pb, 0, SEEK_SET);
        asf_write_header1(s, file_size, file_size - asf->data_offset);
    }

    put_flush_packet(&s->pb);
    return 0;
}

AVOutputFormat asf_oformat = {
    "asf",
    "asf format",
    "video/x-ms-asf",
    "asf,wmv",
    sizeof(ASFContext),
#ifdef CONFIG_MP3LAME
    CODEC_ID_MP3,
#else
    CODEC_ID_MP2,
#endif
    CODEC_ID_MSMPEG4V3,
    asf_write_header,
    asf_write_packet,
    asf_write_trailer,
};

AVOutputFormat asf_stream_oformat = {
    "asf_stream",
    "asf format",
    "video/x-ms-asf",
    "asf,wmv",
    sizeof(ASFContext),
#ifdef CONFIG_MP3LAME
    CODEC_ID_MP3,
#else
    CODEC_ID_MP2,
#endif
    CODEC_ID_MSMPEG4V3,
    asf_write_stream_header,
    asf_write_packet,
    asf_write_trailer,
};
#endif //CONFIG_ENCODERS