PeerStreamer

/*

 * ASF compatible demuxer

 * Copyright (c) 2000, 2001 Fabrice Bellard

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

//#define DEBUG

#include "libavutil/common.h"

#include "libavutil/avstring.h"

#include "libavcodec/mpegaudio.h"

#include "avformat.h"

#include "riff.h"

#include "asf.h"

#include "asfcrypt.h"

#include "avlanguage.h"

void ff_mms_set_stream_selection(URLContext *h, AVFormatContext *format);

typedef struct {

    int asfid2avid[128];                 ///< conversion table from asf ID 2 AVStream ID

    ASFStream streams[128];              ///< it's max number and it's not that big

    uint32_t stream_bitrates[128];       ///< max number of streams, bitrate for each (for streaming)

    AVRational dar[128];

    char stream_languages[128][6];       ///< max number of streams, language for each (RFC1766, e.g. en-US)

    /* non streamed additonnal info */

    /* packet filling */

    int packet_size_left;

    /* only for reading */

    uint64_t data_offset;                ///< beginning of the first data packet

    uint64_t data_object_offset;         ///< data object offset (excl. GUID & size)

    uint64_t data_object_size;           ///< size of the data object

    int index_read;

    ASFMainHeader hdr;

    int packet_flags;

    int packet_property;

    int packet_timestamp;

    int packet_segsizetype;

    int packet_segments;

    int packet_seq;

    int packet_replic_size;

    int packet_key_frame;

    int packet_padsize;

    unsigned int packet_frag_offset;

    unsigned int packet_frag_size;

    int64_t packet_frag_timestamp;

    int packet_multi_size;

    int packet_obj_size;

    int packet_time_delta;

    int packet_time_start;

    int64_t packet_pos;

    int stream_index;

    ASFStream* asf_st;                   ///< currently decoded stream

} ASFContext;

#undef NDEBUG

#include <assert.h>

#define ASF_MAX_STREAMS 127

#define FRAME_HEADER_SIZE 17

// Fix Me! FRAME_HEADER_SIZE may be different.

static const ff_asf_guid index_guid = {

    0x90, 0x08, 0x00, 0x33, 0xb1, 0xe5, 0xcf, 0x11, 0x89, 0xf4, 0x00, 0xa0, 0xc9, 0x03, 0x49, 0xcb

};

static const ff_asf_guid stream_bitrate_guid = { /* (http://get.to/sdp) */

    0xce, 0x75, 0xf8, 0x7b, 0x8d, 0x46, 0xd1, 0x11, 0x8d, 0x82, 0x00, 0x60, 0x97, 0xc9, 0xa2, 0xb2

};

/**********************************/

/* decoding */

#ifdef DEBUG

#define PRINT_IF_GUID(g,cmp) \

if (!ff_guidcmp(g, &cmp)) \

    av_dlog(NULL, "(GUID: %s) ", #cmp)

static void print_guid(const ff_asf_guid *g)

{

    int i;

    PRINT_IF_GUID(g, ff_asf_header);

    else PRINT_IF_GUID(g, ff_asf_file_header);

    else PRINT_IF_GUID(g, ff_asf_stream_header);

    else PRINT_IF_GUID(g, ff_asf_audio_stream);

    else PRINT_IF_GUID(g, ff_asf_audio_conceal_none);

    else PRINT_IF_GUID(g, ff_asf_video_stream);

    else PRINT_IF_GUID(g, ff_asf_video_conceal_none);

    else PRINT_IF_GUID(g, ff_asf_command_stream);

    else PRINT_IF_GUID(g, ff_asf_comment_header);

    else PRINT_IF_GUID(g, ff_asf_codec_comment_header);

    else PRINT_IF_GUID(g, ff_asf_codec_comment1_header);

    else PRINT_IF_GUID(g, ff_asf_data_header);

    else PRINT_IF_GUID(g, index_guid);

    else PRINT_IF_GUID(g, ff_asf_head1_guid);

    else PRINT_IF_GUID(g, ff_asf_head2_guid);

    else PRINT_IF_GUID(g, ff_asf_my_guid);

    else PRINT_IF_GUID(g, ff_asf_ext_stream_header);

    else PRINT_IF_GUID(g, ff_asf_extended_content_header);

    else PRINT_IF_GUID(g, ff_asf_ext_stream_embed_stream_header);

    else PRINT_IF_GUID(g, ff_asf_ext_stream_audio_stream);

    else PRINT_IF_GUID(g, ff_asf_metadata_header);

    else PRINT_IF_GUID(g, ff_asf_marker_header);

    else PRINT_IF_GUID(g, stream_bitrate_guid);

    else PRINT_IF_GUID(g, ff_asf_language_guid);

    else

        av_dlog(NULL, "(GUID: unknown) ");

    for(i=0;i<16;i++)

        av_dlog(NULL, " 0x%02x,", (*g)[i]);

    av_dlog(NULL, "}\n");

}

#undef PRINT_IF_GUID

#else

#define print_guid(g)

#endif

void ff_get_guid(AVIOContext *s, ff_asf_guid *g)

{

    assert(sizeof(*g) == 16);

    avio_read(s, *g, sizeof(*g));

}

static int asf_probe(AVProbeData *pd)

{

    /* check file header */

    if (!ff_guidcmp(pd->buf, &ff_asf_header))

        return AVPROBE_SCORE_MAX;

    else

        return 0;

}

static int get_value(AVIOContext *pb, int type){

    switch(type){

        case 2: return avio_rl32(pb);

        case 3: return avio_rl32(pb);

        case 4: return avio_rl64(pb);

        case 5: return avio_rl16(pb);

        default:return INT_MIN;

    }

}

static void get_tag(AVFormatContext *s, const char *key, int type, int len)

{

    char *value;

    int64_t off = avio_tell(s->pb);

    if ((unsigned)len >= (UINT_MAX - 1)/2)

        return;

    value = av_malloc(2*len+1);

    if (!value)

        goto finish;

    if (type == 0) {         // UTF16-LE

        avio_get_str16le(s->pb, len, value, 2*len + 1);

    } else if (type > 1 && type <= 5) {  // boolean or DWORD or QWORD or WORD

        uint64_t num = get_value(s->pb, type);

        snprintf(value, len, "%"PRIu64, num);

    } else {

        av_log(s, AV_LOG_DEBUG, "Unsupported value type %d in tag %s.\n", type, key);

        goto finish;

    }

    av_metadata_set2(&s->metadata, key, value, 0);

finish:

    av_freep(&value);

    avio_seek(s->pb, off + len, SEEK_SET);

}

static int asf_read_file_properties(AVFormatContext *s, int64_t size)

{

    ASFContext *asf = s->priv_data;

    AVIOContext *pb = s->pb;

    ff_get_guid(pb, &asf->hdr.guid);

    asf->hdr.file_size          = avio_rl64(pb);

    asf->hdr.create_time        = avio_rl64(pb);

    avio_rl64(pb);                               /* number of packets */

    asf->hdr.play_time          = avio_rl64(pb);

    asf->hdr.send_time          = avio_rl64(pb);

    asf->hdr.preroll            = avio_rl32(pb);

    asf->hdr.ignore             = avio_rl32(pb);

    asf->hdr.flags              = avio_rl32(pb);

    asf->hdr.min_pktsize        = avio_rl32(pb);

    asf->hdr.max_pktsize        = avio_rl32(pb);

    asf->hdr.max_bitrate        = avio_rl32(pb);

    s->packet_size = asf->hdr.max_pktsize;

    return 0;

}

static int asf_read_stream_properties(AVFormatContext *s, int64_t size)

{

    ASFContext *asf = s->priv_data;

    AVIOContext *pb = s->pb;

    AVStream *st;

    ASFStream *asf_st;

    ff_asf_guid g;

    enum AVMediaType type;

    int type_specific_size, sizeX;

    uint64_t total_size;

    unsigned int tag1;

    int64_t pos1, pos2, start_time;

    int test_for_ext_stream_audio, is_dvr_ms_audio=0;

    if (s->nb_streams == ASF_MAX_STREAMS) {

        av_log(s, AV_LOG_ERROR, "too many streams\n");

        return AVERROR(EINVAL);

    }

    pos1 = avio_tell(pb);

    st = av_new_stream(s, 0);

    if (!st)

        return AVERROR(ENOMEM);

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

    asf_st = av_mallocz(sizeof(ASFStream));

    if (!asf_st)

        return AVERROR(ENOMEM);

    st->priv_data = asf_st;

    start_time = asf->hdr.preroll;

    asf_st->stream_language_index = 128; // invalid stream index means no language info

    if(!(asf->hdr.flags & 0x01)) { // if we aren't streaming...

        st->duration = asf->hdr.play_time /

            (10000000 / 1000) - start_time;

    }

    ff_get_guid(pb, &g);

    test_for_ext_stream_audio = 0;

    if (!ff_guidcmp(&g, &ff_asf_audio_stream)) {

        type = AVMEDIA_TYPE_AUDIO;

    } else if (!ff_guidcmp(&g, &ff_asf_video_stream)) {

        type = AVMEDIA_TYPE_VIDEO;

    } else if (!ff_guidcmp(&g, &ff_asf_jfif_media)) {

        type = AVMEDIA_TYPE_VIDEO;

        st->codec->codec_id = CODEC_ID_MJPEG;

    } else if (!ff_guidcmp(&g, &ff_asf_command_stream)) {

        type = AVMEDIA_TYPE_DATA;

    } else if (!ff_guidcmp(&g, &ff_asf_ext_stream_embed_stream_header)) {

        test_for_ext_stream_audio = 1;

        type = AVMEDIA_TYPE_UNKNOWN;

    } else {

        return -1;

    }

    ff_get_guid(pb, &g);

    total_size = avio_rl64(pb);

    type_specific_size = avio_rl32(pb);

    avio_rl32(pb);

    st->id = avio_rl16(pb) & 0x7f; /* stream id */

    // mapping of asf ID to AV stream ID;

    asf->asfid2avid[st->id] = s->nb_streams - 1;

    avio_rl32(pb);

    if (test_for_ext_stream_audio) {

        ff_get_guid(pb, &g);

        if (!ff_guidcmp(&g, &ff_asf_ext_stream_audio_stream)) {

            type = AVMEDIA_TYPE_AUDIO;

            is_dvr_ms_audio=1;

            ff_get_guid(pb, &g);

            avio_rl32(pb);

            avio_rl32(pb);

            avio_rl32(pb);

            ff_get_guid(pb, &g);

            avio_rl32(pb);

        }

    }

    st->codec->codec_type = type;

    if (type == AVMEDIA_TYPE_AUDIO) {

        ff_get_wav_header(pb, st->codec, type_specific_size);

        if (is_dvr_ms_audio) {

            // codec_id and codec_tag are unreliable in dvr_ms

            // files. Set them later by probing stream.

            st->codec->codec_id = CODEC_ID_PROBE;

            st->codec->codec_tag = 0;

        }

        if (st->codec->codec_id == CODEC_ID_AAC) {

            st->need_parsing = AVSTREAM_PARSE_NONE;

        } else {

            st->need_parsing = AVSTREAM_PARSE_FULL;

        }

        /* We have to init the frame size at some point .... */

        pos2 = avio_tell(pb);

        if (size >= (pos2 + 8 - pos1 + 24)) {

            asf_st->ds_span = avio_r8(pb);

            asf_st->ds_packet_size = avio_rl16(pb);

            asf_st->ds_chunk_size = avio_rl16(pb);

            avio_rl16(pb); //ds_data_size

            avio_r8(pb);   //ds_silence_data

        }

        //printf("Descrambling: ps:%d cs:%d ds:%d s:%d  sd:%d\n",

        //       asf_st->ds_packet_size, asf_st->ds_chunk_size,

        //       asf_st->ds_data_size, asf_st->ds_span, asf_st->ds_silence_data);

        if (asf_st->ds_span > 1) {

            if (!asf_st->ds_chunk_size

                    || (asf_st->ds_packet_size/asf_st->ds_chunk_size <= 1)

                    || asf_st->ds_packet_size % asf_st->ds_chunk_size)

                asf_st->ds_span = 0; // disable descrambling

        }

        switch (st->codec->codec_id) {

            case CODEC_ID_MP3:

                st->codec->frame_size = MPA_FRAME_SIZE;

                break;

            case CODEC_ID_PCM_S16LE:

            case CODEC_ID_PCM_S16BE:

            case CODEC_ID_PCM_U16LE:

            case CODEC_ID_PCM_U16BE:

            case CODEC_ID_PCM_S8:

            case CODEC_ID_PCM_U8:

            case CODEC_ID_PCM_ALAW:

            case CODEC_ID_PCM_MULAW:

                st->codec->frame_size = 1;

                break;

            default:

                /* This is probably wrong, but it prevents a crash later */

                st->codec->frame_size = 1;

                break;

        }

    } else if (type == AVMEDIA_TYPE_VIDEO &&

            size - (avio_tell(pb) - pos1 + 24) >= 51) {

        avio_rl32(pb);

        avio_rl32(pb);

        avio_r8(pb);

        avio_rl16(pb);        /* size */

        sizeX= avio_rl32(pb); /* size */

        st->codec->width = avio_rl32(pb);

        st->codec->height = avio_rl32(pb);

        /* not available for asf */

        avio_rl16(pb); /* panes */

        st->codec->bits_per_coded_sample = avio_rl16(pb); /* depth */

        tag1 = avio_rl32(pb);

        avio_skip(pb, 20);

        //                av_log(s, AV_LOG_DEBUG, "size:%d tsize:%d sizeX:%d\n", size, total_size, sizeX);

        if (sizeX > 40) {

            st->codec->extradata_size = sizeX - 40;

            st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

            avio_read(pb, st->codec->extradata, st->codec->extradata_size);

        }

        /* Extract palette from extradata if bpp <= 8 */

        /* This code assumes that extradata contains only palette */

        /* This is true for all paletted codecs implemented in ffmpeg */

        if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {

            int av_unused i;

            st->codec->palctrl = av_mallocz(sizeof(AVPaletteControl));

#if HAVE_BIGENDIAN

            for (i = 0; i < FFMIN(st->codec->extradata_size, AVPALETTE_SIZE)/4; i++)

                st->codec->palctrl->palette[i] = av_bswap32(((uint32_t*)st->codec->extradata)[i]);

#else

            memcpy(st->codec->palctrl->palette, st->codec->extradata,

                    FFMIN(st->codec->extradata_size, AVPALETTE_SIZE));

#endif

            st->codec->palctrl->palette_changed = 1;

        }

        st->codec->codec_tag = tag1;

        st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tag1);

        if(tag1 == MKTAG('D', 'V', 'R', ' ')){

            st->need_parsing = AVSTREAM_PARSE_FULL;

            // issue658 containse wrong w/h and MS even puts a fake seq header with wrong w/h in extradata while a correct one is in te stream. maximum lameness

            st->codec->width  =

                st->codec->height = 0;

            av_freep(&st->codec->extradata);

            st->codec->extradata_size=0;

        }

        if(st->codec->codec_id == CODEC_ID_H264)

            st->need_parsing = AVSTREAM_PARSE_FULL_ONCE;

    }

    pos2 = avio_tell(pb);

    avio_skip(pb, size - (pos2 - pos1 + 24));

    return 0;

}

static int asf_read_ext_stream_properties(AVFormatContext *s, int64_t size)

{

    ASFContext *asf = s->priv_data;

    AVIOContext *pb = s->pb;

    ff_asf_guid g;

    int ext_len, payload_ext_ct, stream_ct, i;

    uint32_t ext_d, leak_rate, stream_num;

    unsigned int stream_languageid_index;

    avio_rl64(pb); // starttime

    avio_rl64(pb); // endtime

    leak_rate = avio_rl32(pb); // leak-datarate

    avio_rl32(pb); // bucket-datasize

    avio_rl32(pb); // init-bucket-fullness

    avio_rl32(pb); // alt-leak-datarate

    avio_rl32(pb); // alt-bucket-datasize

    avio_rl32(pb); // alt-init-bucket-fullness

    avio_rl32(pb); // max-object-size

    avio_rl32(pb); // flags (reliable,seekable,no_cleanpoints?,resend-live-cleanpoints, rest of bits reserved)

    stream_num = avio_rl16(pb); // stream-num

    stream_languageid_index = avio_rl16(pb); // stream-language-id-index

    if (stream_num < 128)

        asf->streams[stream_num].stream_language_index = stream_languageid_index;

    avio_rl64(pb); // avg frametime in 100ns units

    stream_ct = avio_rl16(pb); //stream-name-count

    payload_ext_ct = avio_rl16(pb); //payload-extension-system-count

    if (stream_num < 128)

        asf->stream_bitrates[stream_num] = leak_rate;

    for (i=0; i<stream_ct; i++){

        avio_rl16(pb);

        ext_len = avio_rl16(pb);

        avio_skip(pb, ext_len);

    }

    for (i=0; i<payload_ext_ct; i++){

        ff_get_guid(pb, &g);

        ext_d=avio_rl16(pb);

        ext_len=avio_rl32(pb);

        avio_skip(pb, ext_len);

    }

    return 0;

}

static int asf_read_content_desc(AVFormatContext *s, int64_t size)

{

    AVIOContext *pb = s->pb;

    int len1, len2, len3, len4, len5;

    len1 = avio_rl16(pb);

    len2 = avio_rl16(pb);

    len3 = avio_rl16(pb);

    len4 = avio_rl16(pb);

    len5 = avio_rl16(pb);

    get_tag(s, "title"    , 0, len1);

    get_tag(s, "author"   , 0, len2);

    get_tag(s, "copyright", 0, len3);

    get_tag(s, "comment"  , 0, len4);

    avio_skip(pb, len5);

    return 0;

}

static int asf_read_ext_content_desc(AVFormatContext *s, int64_t size)

{

    AVIOContext *pb = s->pb;

    ASFContext *asf = s->priv_data;

    int desc_count, i, ret;

    desc_count = avio_rl16(pb);

    for(i=0;i<desc_count;i++) {

        int name_len,value_type,value_len;

        char name[1024];

        name_len = avio_rl16(pb);

        if (name_len%2)     // must be even, broken lavf versions wrote len-1

            name_len += 1;

        if ((ret = avio_get_str16le(pb, name_len, name, sizeof(name))) < name_len)

            avio_skip(pb, name_len - ret);

        value_type = avio_rl16(pb);

        value_len  = avio_rl16(pb);

        if (!value_type && value_len%2)

            value_len += 1;

        /**

         * My sample has that stream set to 0 maybe that mean the container.

         * Asf stream count start at 1. I am using 0 to the container value since it's unused

         */

        if (!strcmp(name, "AspectRatioX")){

            asf->dar[0].num= get_value(s->pb, value_type);

        } else if(!strcmp(name, "AspectRatioY")){

            asf->dar[0].den= get_value(s->pb, value_type);

        } else

            get_tag(s, name, value_type, value_len);

    }

    return 0;

}

static int asf_read_language_list(AVFormatContext *s, int64_t size)

{

    AVIOContext *pb = s->pb;

    ASFContext *asf = s->priv_data;

    int j, ret;

    int stream_count = avio_rl16(pb);

    for(j = 0; j < stream_count; j++) {

        char lang[6];

        unsigned int lang_len = avio_r8(pb);

        if ((ret = avio_get_str16le(pb, lang_len, lang, sizeof(lang))) < lang_len)

            avio_skip(pb, lang_len - ret);

        if (j < 128)

            av_strlcpy(asf->stream_languages[j], lang, sizeof(*asf->stream_languages));

    }

    return 0;

}

static int asf_read_metadata(AVFormatContext *s, int64_t size)

{

    AVIOContext *pb = s->pb;

    ASFContext *asf = s->priv_data;

    int n, stream_num, name_len, value_len, value_type, value_num;

    int ret, i;

    n = avio_rl16(pb);

    for(i=0;i<n;i++) {

        char name[1024];

        avio_rl16(pb); //lang_list_index

        stream_num= avio_rl16(pb);

        name_len=   avio_rl16(pb);

        value_type= avio_rl16(pb);

        value_len=  avio_rl32(pb);

        if ((ret = avio_get_str16le(pb, name_len, name, sizeof(name))) < name_len)

            avio_skip(pb, name_len - ret);

        //av_log(s, AV_LOG_ERROR, "%d %d %d %d %d <%s>\n", i, stream_num, name_len, value_type, value_len, name);

        value_num= avio_rl16(pb);//we should use get_value() here but it does not work 2 is le16 here but le32 elsewhere

        avio_skip(pb, value_len - 2);

        if(stream_num<128){

            if     (!strcmp(name, "AspectRatioX")) asf->dar[stream_num].num= value_num;

            else if(!strcmp(name, "AspectRatioY")) asf->dar[stream_num].den= value_num;

        }

    }

    return 0;

}

static int asf_read_marker(AVFormatContext *s, int64_t size)

{

    AVIOContext *pb = s->pb;

    int i, count, name_len, ret;

    char name[1024];

    avio_rl64(pb);            // reserved 16 bytes

    avio_rl64(pb);            // ...

    count = avio_rl32(pb);    // markers count

    avio_rl16(pb);            // reserved 2 bytes

    name_len = avio_rl16(pb); // name length

    for(i=0;i<name_len;i++){

        avio_r8(pb); // skip the name

    }

    for(i=0;i<count;i++){

        int64_t pres_time;

        int name_len;

        avio_rl64(pb);             // offset, 8 bytes

        pres_time = avio_rl64(pb); // presentation time

        avio_rl16(pb);             // entry length

        avio_rl32(pb);             // send time

        avio_rl32(pb);             // flags

        name_len = avio_rl32(pb);  // name length

        if ((ret = avio_get_str16le(pb, name_len * 2, name, sizeof(name))) < name_len)

            avio_skip(pb, name_len - ret);

        ff_new_chapter(s, i, (AVRational){1, 10000000}, pres_time, AV_NOPTS_VALUE, name );

    }

    return 0;

}

static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)

{

    ASFContext *asf = s->priv_data;

    ff_asf_guid g;

    AVIOContext *pb = s->pb;

    int i;

    int64_t gsize;

    ff_get_guid(pb, &g);

    if (ff_guidcmp(&g, &ff_asf_header))

        return -1;

    avio_rl64(pb);

    avio_rl32(pb);

    avio_r8(pb);

    avio_r8(pb);

    memset(&asf->asfid2avid, -1, sizeof(asf->asfid2avid));

    for(;;) {

        uint64_t gpos= avio_tell(pb);

        ff_get_guid(pb, &g);

        gsize = avio_rl64(pb);

        av_dlog(s, "%08"PRIx64": ", gpos);

        print_guid(&g);

        av_dlog(s, "  size=0x%"PRIx64"\n", gsize);

        if (!ff_guidcmp(&g, &ff_asf_data_header)) {

            asf->data_object_offset = avio_tell(pb);

            // if not streaming, gsize is not unlimited (how?), and there is enough space in the file..

            if (!(asf->hdr.flags & 0x01) && gsize >= 100) {

                asf->data_object_size = gsize - 24;

            } else {

                asf->data_object_size = (uint64_t)-1;

            }

            break;

        }

        if (gsize < 24)

            return -1;

        if (!ff_guidcmp(&g, &ff_asf_file_header)) {

            asf_read_file_properties(s, gsize);

        } else if (!ff_guidcmp(&g, &ff_asf_stream_header)) {

            asf_read_stream_properties(s, gsize);

        } else if (!ff_guidcmp(&g, &ff_asf_comment_header)) {

            asf_read_content_desc(s, gsize);

        } else if (!ff_guidcmp(&g, &ff_asf_language_guid)) {

            asf_read_language_list(s, gsize);

        } else if (!ff_guidcmp(&g, &ff_asf_extended_content_header)) {

            asf_read_ext_content_desc(s, gsize);

        } else if (!ff_guidcmp(&g, &ff_asf_metadata_header)) {

            asf_read_metadata(s, gsize);

        } else if (!ff_guidcmp(&g, &ff_asf_ext_stream_header)) {

            asf_read_ext_stream_properties(s, gsize);

            // there could be a optional stream properties object to follow

            // if so the next iteration will pick it up

            continue;

        } else if (!ff_guidcmp(&g, &ff_asf_head1_guid)) {

            int v1, v2;

            ff_get_guid(pb, &g);

            v1 = avio_rl32(pb);

            v2 = avio_rl16(pb);

            continue;

        } else if (!ff_guidcmp(&g, &ff_asf_marker_header)) {

            asf_read_marker(s, gsize);

        } else if (url_feof(pb)) {

            return -1;

        } else {

            if (!s->keylen) {

                if (!ff_guidcmp(&g, &ff_asf_content_encryption)) {

                    av_log(s, AV_LOG_WARNING, "DRM protected stream detected, decoding will likely fail!\n");

                } else if (!ff_guidcmp(&g, &ff_asf_ext_content_encryption)) {

                    av_log(s, AV_LOG_WARNING, "Ext DRM protected stream detected, decoding will likely fail!\n");

                } else if (!ff_guidcmp(&g, &ff_asf_digital_signature)) {

                    av_log(s, AV_LOG_WARNING, "Digital signature detected, decoding will likely fail!\n");

                }

            }

        }

        if(avio_tell(pb) != gpos + gsize)

            av_log(s, AV_LOG_DEBUG, "gpos mismatch our pos=%"PRIu64", end=%"PRIu64"\n", avio_tell(pb)-gpos, gsize);

        avio_seek(pb, gpos + gsize, SEEK_SET);

    }

    ff_get_guid(pb, &g);

    avio_rl64(pb);

    avio_r8(pb);

    avio_r8(pb);

    if (url_feof(pb))

        return -1;

    asf->data_offset = avio_tell(pb);

    asf->packet_size_left = 0;

    for(i=0; i<128; i++){

        int stream_num= asf->asfid2avid[i];

        if(stream_num>=0){

            AVStream *st = s->streams[stream_num];

            if (!st->codec->bit_rate)

                st->codec->bit_rate = asf->stream_bitrates[i];

            if (asf->dar[i].num > 0 && asf->dar[i].den > 0){

                av_reduce(&st->sample_aspect_ratio.num,

                          &st->sample_aspect_ratio.den,

                          asf->dar[i].num, asf->dar[i].den, INT_MAX);

            } else if ((asf->dar[0].num > 0) && (asf->dar[0].den > 0) && (st->codec->codec_type==AVMEDIA_TYPE_VIDEO)) // Use ASF container value if the stream doesn't AR set.

                av_reduce(&st->sample_aspect_ratio.num,

                          &st->sample_aspect_ratio.den,

                          asf->dar[0].num, asf->dar[0].den, INT_MAX);

//av_log(s, AV_LOG_INFO, "i=%d, st->codec->codec_type:%d, dar %d:%d sar=%d:%d\n", i, st->codec->codec_type, dar[i].num, dar[i].den, st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);

            // copy and convert language codes to the frontend

            if (asf->streams[i].stream_language_index < 128) {

                const char *rfc1766 = asf->stream_languages[asf->streams[i].stream_language_index];

                if (rfc1766 && strlen(rfc1766) > 1) {

                    const char primary_tag[3] = { rfc1766[0], rfc1766[1], '\0' }; // ignore country code if any

                    const char *iso6392 = av_convert_lang_to(primary_tag, AV_LANG_ISO639_2_BIBL);

                    if (iso6392)

                        av_metadata_set2(&st->metadata, "language", iso6392, 0);

                }

            }

        }

    }

    ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);

    return 0;

}

#define DO_2BITS(bits, var, defval) \

    switch (bits & 3) \

    { \

    case 3: var = avio_rl32(pb); rsize += 4; break; \

    case 2: var = avio_rl16(pb); rsize += 2; break; \

    case 1: var = avio_r8(pb);   rsize++; break; \

    default: var = defval; break; \

    }

/**

 * Load a single ASF packet into the demuxer.

 * @param s demux context

 * @param pb context to read data from

 * @return 0 on success, <0 on error

 */

static int ff_asf_get_packet(AVFormatContext *s, AVIOContext *pb)

{

    ASFContext *asf = s->priv_data;

    uint32_t packet_length, padsize;

    int rsize = 8;

    int c, d, e, off;

    // if we do not know packet size, allow skipping up to 32 kB

    off= 32768;

    if (s->packet_size > 0)

        off= (avio_tell(pb) - s->data_offset) % s->packet_size + 3;

    c=d=e=-1;

    while(off-- > 0){

        c=d; d=e;

        e= avio_r8(pb);

        if(c == 0x82 && !d && !e)

            break;

    }

    if (c != 0x82) {

        /**

         * This code allows handling of -EAGAIN at packet boundaries (i.e.

         * if the packet sync code above triggers -EAGAIN). This does not

         * imply complete -EAGAIN handling support at random positions in

         * the stream.

         */

        if (pb->error == AVERROR(EAGAIN))

            return AVERROR(EAGAIN);

        if (!url_feof(pb))

            av_log(s, AV_LOG_ERROR, "ff asf bad header %x  at:%"PRId64"\n", c, avio_tell(pb));

    }

    if ((c & 0x8f) == 0x82) {

        if (d || e) {

            if (!url_feof(pb))

                av_log(s, AV_LOG_ERROR, "ff asf bad non zero\n");

            return -1;

        }

        c= avio_r8(pb);

        d= avio_r8(pb);

        rsize+=3;

    }else{

        avio_seek(pb, -1, SEEK_CUR); //FIXME

    }

    asf->packet_flags    = c;

    asf->packet_property = d;

    DO_2BITS(asf->packet_flags >> 5, packet_length, s->packet_size);

    DO_2BITS(asf->packet_flags >> 1, padsize, 0); // sequence ignored

    DO_2BITS(asf->packet_flags >> 3, padsize, 0); // padding length

    //the following checks prevent overflows and infinite loops

    if(!packet_length || packet_length >= (1U<<29)){

        av_log(s, AV_LOG_ERROR, "invalid packet_length %d at:%"PRId64"\n", packet_length, avio_tell(pb));

        return -1;

    }

    if(padsize >= packet_length){

        av_log(s, AV_LOG_ERROR, "invalid padsize %d at:%"PRId64"\n", padsize, avio_tell(pb));

        return -1;

    }

    asf->packet_timestamp = avio_rl32(pb);

    avio_rl16(pb); /* duration */

    // rsize has at least 11 bytes which have to be present

    if (asf->packet_flags & 0x01) {

        asf->packet_segsizetype = avio_r8(pb); rsize++;

        asf->packet_segments = asf->packet_segsizetype & 0x3f;

    } else {

        asf->packet_segments = 1;

        asf->packet_segsizetype = 0x80;

    }

    asf->packet_size_left = packet_length - padsize - rsize;

    if (packet_length < asf->hdr.min_pktsize)

        padsize += asf->hdr.min_pktsize - packet_length;

    asf->packet_padsize = padsize;

    av_dlog(s, "packet: size=%d padsize=%d  left=%d\n", s->packet_size, asf->packet_padsize, asf->packet_size_left);

    return 0;

}

/**

 *

 * @return <0 if error

 */

static int asf_read_frame_header(AVFormatContext *s, AVIOContext *pb){

    ASFContext *asf = s->priv_data;

    int rsize = 1;

    int num = avio_r8(pb);

    int64_t ts0, ts1;

    asf->packet_segments--;

    asf->packet_key_frame = num >> 7;

    asf->stream_index = asf->asfid2avid[num & 0x7f];

    // sequence should be ignored!

    DO_2BITS(asf->packet_property >> 4, asf->packet_seq, 0);

    DO_2BITS(asf->packet_property >> 2, asf->packet_frag_offset, 0);

    DO_2BITS(asf->packet_property, asf->packet_replic_size, 0);

//printf("key:%d stream:%d seq:%d offset:%d replic_size:%d\n", asf->packet_key_frame, asf->stream_index, asf->packet_seq, //asf->packet_frag_offset, asf->packet_replic_size);

    if (asf->packet_replic_size >= 8) {

        asf->packet_obj_size = avio_rl32(pb);

        if(asf->packet_obj_size >= (1<<24) || asf->packet_obj_size <= 0){

            av_log(s, AV_LOG_ERROR, "packet_obj_size invalid\n");

            return -1;

        }

        asf->packet_frag_timestamp = avio_rl32(pb); // timestamp

        if(asf->packet_replic_size >= 8+38+4){

//            for(i=0; i<asf->packet_replic_size-8; i++)

//                av_log(s, AV_LOG_DEBUG, "%02X ",avio_r8(pb));

//            av_log(s, AV_LOG_DEBUG, "\n");

            avio_skip(pb, 10);

            ts0= avio_rl64(pb);

            ts1= avio_rl64(pb);

            avio_skip(pb, 12);

            avio_rl32(pb);

            avio_skip(pb, asf->packet_replic_size - 8 - 38 - 4);

            if(ts0!= -1) asf->packet_frag_timestamp= ts0/10000;

            else         asf->packet_frag_timestamp= AV_NOPTS_VALUE;

        }else

            avio_skip(pb, asf->packet_replic_size - 8);

        rsize += asf->packet_replic_size; // FIXME - check validity

    } else if (asf->packet_replic_size==1){

        // multipacket - frag_offset is beginning timestamp

        asf->packet_time_start = asf->packet_frag_offset;

        asf->packet_frag_offset = 0;

        asf->packet_frag_timestamp = asf->packet_timestamp;

        asf->packet_time_delta = avio_r8(pb);

        rsize++;

    }else if(asf->packet_replic_size!=0){

        av_log(s, AV_LOG_ERROR, "unexpected packet_replic_size of %d\n", asf->packet_replic_size);

        return -1;

    }

    if (asf->packet_flags & 0x01) {

        DO_2BITS(asf->packet_segsizetype >> 6, asf->packet_frag_size, 0); // 0 is illegal

        if(asf->packet_frag_size > asf->packet_size_left - rsize){

            av_log(s, AV_LOG_ERROR, "packet_frag_size is invalid\n");

            return -1;

        }

        //printf("Fragsize %d\n", asf->packet_frag_size);

    } else {

        asf->packet_frag_size = asf->packet_size_left - rsize;

        //printf("Using rest  %d %d %d\n", asf->packet_frag_size, asf->packet_size_left, rsize);

    }

    if (asf->packet_replic_size == 1) {

        asf->packet_multi_size = asf->packet_frag_size;

        if (asf->packet_multi_size > asf->packet_size_left)

            return -1;

    }

    asf->packet_size_left -= rsize;

    //printf("___objsize____  %d   %d    rs:%d\n", asf->packet_obj_size, asf->packet_frag_offset, rsize);

    return 0;

}

/**

 * Parse data from individual ASF packets (which were previously loaded

 * with asf_get_packet()).

 * @param s demux context

 * @param pb context to read data from

 * @param pkt pointer to store packet data into

 * @return 0 if data was stored in pkt, <0 on error or 1 if more ASF

 *          packets need to be loaded (through asf_get_packet())

 */

static int ff_asf_parse_packet(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)

{

    ASFContext *asf = s->priv_data;

    ASFStream *asf_st = 0;

    for (;;) {

        int ret;

        if(url_feof(pb))

            return AVERROR_EOF;

        if (asf->packet_size_left < FRAME_HEADER_SIZE

            || asf->packet_segments < 1) {

            //asf->packet_size_left <= asf->packet_padsize) {

            int ret = asf->packet_size_left + asf->packet_padsize;

            //printf("PacketLeftSize:%d  Pad:%d Pos:%"PRId64"\n", asf->packet_size_left, asf->packet_padsize, avio_tell(pb));

            assert(ret>=0);

            /* fail safe */

            avio_skip(pb, ret);

            asf->packet_pos= avio_tell(pb);

            if (asf->data_object_size != (uint64_t)-1 &&

                (asf->packet_pos - asf->data_object_offset >= asf->data_object_size))

                return AVERROR_EOF; /* Do not exceed the size of the data object */

            return 1;

        }

        if (asf->packet_time_start == 0) {

            if(asf_read_frame_header(s, pb) < 0){

                asf->packet_segments= 0;

                continue;

            }

            if (asf->stream_index < 0

                || s->streams[asf->stream_index]->discard >= AVDISCARD_ALL

                || (!asf->packet_key_frame && s->streams[asf->stream_index]->discard >= AVDISCARD_NONKEY)

                ) {

                asf->packet_time_start = 0;

                /* unhandled packet (should not happen) */

                avio_skip(pb, asf->packet_frag_size);

                asf->packet_size_left -= asf->packet_frag_size;

                if(asf->stream_index < 0)

                    av_log(s, AV_LOG_ERROR, "ff asf skip %d (unknown stream)\n", asf->packet_frag_size);

                continue;

            }

            asf->asf_st = s->streams[asf->stream_index]->priv_data;

        }

        asf_st = asf->asf_st;

        if (asf->packet_replic_size == 1) {

            // frag_offset is here used as the beginning timestamp

            asf->packet_frag_timestamp = asf->packet_time_start;

            asf->packet_time_start += asf->packet_time_delta;

            asf->packet_obj_size = asf->packet_frag_size = avio_r8(pb);

            asf->packet_size_left--;

            asf->packet_multi_size--;

            if (asf->packet_multi_size < asf->packet_obj_size)

            {

                asf->packet_time_start = 0;

                avio_skip(pb, asf->packet_multi_size);

                asf->packet_size_left -= asf->packet_multi_size;

                continue;

            }

            asf->packet_multi_size -= asf->packet_obj_size;

            //printf("COMPRESS size  %d  %d  %d   ms:%d\n", asf->packet_obj_size, asf->packet_frag_timestamp, asf->packet_size_left, asf->packet_multi_size);

        }

        if(   /*asf->packet_frag_size == asf->packet_obj_size*/

              asf_st->frag_offset + asf->packet_frag_size <= asf_st->pkt.size

           && asf_st->frag_offset + asf->packet_frag_size > asf->packet_obj_size){

            av_log(s, AV_LOG_INFO, "ignoring invalid packet_obj_size (%d %d %d %d)\n",

                asf_st->frag_offset, asf->packet_frag_size,

                asf->packet_obj_size, asf_st->pkt.size);

            asf->packet_obj_size= asf_st->pkt.size;

        }

        if (   asf_st->pkt.size != asf->packet_obj_size

            || asf_st->frag_offset + asf->packet_frag_size > asf_st->pkt.size) { //FIXME is this condition sufficient?

            if(asf_st->pkt.data){

                av_log(s, AV_LOG_INFO, "freeing incomplete packet size %d, new %d\n", asf_st->pkt.size, asf->packet_obj_size);

                asf_st->frag_offset = 0;

                av_free_packet(&asf_st->pkt);

            }

            /* new packet */

            av_new_packet(&asf_st->pkt, asf->packet_obj_size);

            asf_st->seq = asf->packet_seq;

            asf_st->pkt.dts = asf->packet_frag_timestamp - asf->hdr.preroll;

            asf_st->pkt.stream_index = asf->stream_index;

            asf_st->pkt.pos =

            asf_st->packet_pos= asf->packet_pos;

//printf("new packet: stream:%d key:%d packet_key:%d audio:%d size:%d\n",

//asf->stream_index, asf->packet_key_frame, asf_st->pkt.flags & AV_PKT_FLAG_KEY,

//s->streams[asf->stream_index]->codec->codec_type == AVMEDIA_TYPE_AUDIO, asf->packet_obj_size);

            if (s->streams[asf->stream_index]->codec->codec_type == AVMEDIA_TYPE_AUDIO)

                asf->packet_key_frame = 1;

            if (asf->packet_key_frame)

                asf_st->pkt.flags |= AV_PKT_FLAG_KEY;

        }

        /* read data */

        //printf("READ PACKET s:%d  os:%d  o:%d,%d  l:%d   DATA:%p\n",

        //       s->packet_size, asf_st->pkt.size, asf->packet_frag_offset,

        //       asf_st->frag_offset, asf->packet_frag_size, asf_st->pkt.data);

        asf->packet_size_left -= asf->packet_frag_size;

        if (asf->packet_size_left < 0)

            continue;

        if(   asf->packet_frag_offset >= asf_st->pkt.size

           || asf->packet_frag_size > asf_st->pkt.size - asf->packet_frag_offset){

            av_log(s, AV_LOG_ERROR, "packet fragment position invalid %u,%u not in %u\n",

                asf->packet_frag_offset, asf->packet_frag_size, asf_st->pkt.size);

            continue;

        }

        ret = avio_read(pb, asf_st->pkt.data + asf->packet_frag_offset,

                         asf->packet_frag_size);

        if (ret != asf->packet_frag_size) {

            if (ret < 0 || asf->packet_frag_offset + ret == 0)

                return ret < 0 ? ret : AVERROR_EOF;

            if (asf_st->ds_span > 1) {

                // scrambling, we can either drop it completely or fill the remainder

                // TODO: should we fill the whole packet instead of just the current

                // fragment?

                memset(asf_st->pkt.data + asf->packet_frag_offset + ret, 0,

                       asf->packet_frag_size - ret);

                ret = asf->packet_frag_size;

            } else

                // no scrambling, so we can return partial packets

                av_shrink_packet(&asf_st->pkt, asf->packet_frag_offset + ret);

        }

        if (s->key && s->keylen == 20)

            ff_asfcrypt_dec(s->key, asf_st->pkt.data + asf->packet_frag_offset,

                            ret);

        asf_st->frag_offset += ret;

        /* test if whole packet is read */

        if (asf_st->frag_offset == asf_st->pkt.size) {

            //workaround for macroshit radio DVR-MS files

            if(   s->streams[asf->stream_index]->codec->codec_id == CODEC_ID_MPEG2VIDEO

               && asf_st->pkt.size > 100){

                int i;

                for(i=0; i<asf_st->pkt.size && !asf_st->pkt.data[i]; i++);

                if(i == asf_st->pkt.size){

                    av_log(s, AV_LOG_DEBUG, "discarding ms fart\n");

                    asf_st->frag_offset = 0;

                    av_free_packet(&asf_st->pkt);

                    continue;

                }

            }

            /* return packet */

            if (asf_st->ds_span > 1) {

              if(asf_st->pkt.size != asf_st->ds_packet_size * asf_st->ds_span){

                    av_log(s, AV_LOG_ERROR, "pkt.size != ds_packet_size * ds_span (%d %d %d)\n", asf_st->pkt.size, asf_st->ds_packet_size, asf_st->ds_span);

              }else{

                /* packet descrambling */

                uint8_t *newdata = av_malloc(asf_st->pkt.size + FF_INPUT_BUFFER_PADDING_SIZE);

                if (newdata) {

                    int offset = 0;

                    memset(newdata + asf_st->pkt.size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

                    while (offset < asf_st->pkt.size) {

                        int off = offset / asf_st->ds_chunk_size;

                        int row = off / asf_st->ds_span;

                        int col = off % asf_st->ds_span;

                        int idx = row + col * asf_st->ds_packet_size / asf_st->ds_chunk_size;

                        //printf("off:%d  row:%d  col:%d  idx:%d\n", off, row, col, idx);

                        assert(offset + asf_st->ds_chunk_size <= asf_st->pkt.size);

                        assert(idx+1 <= asf_st->pkt.size / asf_st->ds_chunk_size);

                        memcpy(newdata + offset,

                               asf_st->pkt.data + idx * asf_st->ds_chunk_size,

                               asf_st->ds_chunk_size);

                        offset += asf_st->ds_chunk_size;

                    }

                    av_free(asf_st->pkt.data);

                    asf_st->pkt.data = newdata;

                }

              }

            }

            asf_st->frag_offset = 0;

            *pkt= asf_st->pkt;

            //printf("packet %d %d\n", asf_st->pkt.size, asf->packet_frag_size);

            asf_st->pkt.size = 0;

            asf_st->pkt.data = 0;

            break; // packet completed

        }

    }

    return 0;

}

static int asf_read_packet(AVFormatContext *s, AVPacket *pkt)

{

    ASFContext *asf = s->priv_data;

    for (;;) {

        int ret;

        /* parse cached packets, if any */

        if ((ret = ff_asf_parse_packet(s, s->pb, pkt)) <= 0)

            return ret;

        if ((ret = ff_asf_get_packet(s, s->pb)) < 0)

            assert(asf->packet_size_left < FRAME_HEADER_SIZE || asf->packet_segments < 1);

        asf->packet_time_start = 0;

    }

    return 0;

}

// Added to support seeking after packets have been read

// If information is not reset, read_packet fails due to

// leftover information from previous reads

static void asf_reset_header(AVFormatContext *s)

{

    ASFContext *asf = s->priv_data;

    ASFStream *asf_st;

    int i;

    asf->packet_size_left = 0;

    asf->packet_segments = 0;

    asf->packet_flags = 0;

    asf->packet_property = 0;

    asf->packet_timestamp = 0;

    asf->packet_segsizetype = 0;

    asf->packet_segments = 0;

    asf->packet_seq = 0;

    asf->packet_replic_size = 0;

    asf->packet_key_frame = 0;

    asf->packet_padsize = 0;

    asf->packet_frag_offset = 0;

    asf->packet_frag_size = 0;

    asf->packet_frag_timestamp = 0;

    asf->packet_multi_size = 0;

    asf->packet_obj_size = 0;

    asf->packet_time_delta = 0;

    asf->packet_time_start = 0;

    for(i=0; i<s->nb_streams; i++){

        asf_st= s->streams[i]->priv_data;

        av_free_packet(&asf_st->pkt);

        asf_st->frag_offset=0;

        asf_st->seq=0;

    }

    asf->asf_st= NULL;

}

static int asf_read_close(AVFormatContext *s)

{

    int i;

    asf_reset_header(s);

    for(i=0;i<s->nb_streams;i++) {

        AVStream *st = s->streams[i];

        av_free(st->codec->palctrl);

    }

    return 0;

}

static int64_t asf_read_pts(AVFormatContext *s, int stream_index, int64_t *ppos, int64_t pos_limit)

{

    AVPacket pkt1, *pkt = &pkt1;

    ASFStream *asf_st;

    int64_t pts;

    int64_t pos= *ppos;

    int i;

    int64_t start_pos[ASF_MAX_STREAMS];

    for(i=0; i<s->nb_streams; i++){

        start_pos[i]= pos;

    }

    if (s->packet_size > 0)

        pos= (pos+s->packet_size-1-s->data_offset)/s->packet_size*s->packet_size+ s->data_offset;

    *ppos= pos;

    avio_seek(s->pb, pos, SEEK_SET);

//printf("asf_read_pts\n");

    asf_reset_header(s);

    for(;;){

        if (av_read_frame(s, pkt) < 0){

            av_log(s, AV_LOG_INFO, "asf_read_pts failed\n");

            return AV_NOPTS_VALUE;

        }

        pts= pkt->pts;

        av_free_packet(pkt);

        if(pkt->flags&AV_PKT_FLAG_KEY){

            i= pkt->stream_index;

            asf_st= s->streams[i]->priv_data;

//            assert((asf_st->packet_pos - s->data_offset) % s->packet_size == 0);

            pos= asf_st->packet_pos;

            av_add_index_entry(s->streams[i], pos, pts, pkt->size, pos - start_pos[i] + 1, AVINDEX_KEYFRAME);

            start_pos[i]= asf_st->packet_pos + 1;

            if(pkt->stream_index == stream_index)

               break;

        }

    }

    *ppos= pos;

//printf("found keyframe at %"PRId64" stream %d stamp:%"PRId64"\n", *ppos, stream_index, pts);

    return pts;

}

static void asf_build_simple_index(AVFormatContext *s, int stream_index)

{

    ff_asf_guid g;

    ASFContext *asf = s->priv_data;

    int64_t current_pos= avio_tell(s->pb);

    int i;

    avio_seek(s->pb, asf->data_object_offset + asf->data_object_size, SEEK_SET);

    ff_get_guid(s->pb, &g);

    /* the data object can be followed by other top-level objects,

       skip them until the simple index object is reached */

    while (ff_guidcmp(&g, &index_guid)) {

        int64_t gsize= avio_rl64(s->pb);

        if (gsize < 24 || url_feof(s->pb)) {

            avio_seek(s->pb, current_pos, SEEK_SET);

            return;

        }

        avio_skip(s->pb, gsize-24);

        ff_get_guid(s->pb, &g);

    }

    {

        int64_t itime, last_pos=-1;

        int pct, ict;

        int64_t av_unused gsize= avio_rl64(s->pb);

        ff_get_guid(s->pb, &g);

        itime=avio_rl64(s->pb);

        pct=avio_rl32(s->pb);

        ict=avio_rl32(s->pb);

        av_log(s, AV_LOG_DEBUG, "itime:0x%"PRIx64", pct:%d, ict:%d\n",itime,pct,ict);

        for (i=0;i<ict;i++){

            int pktnum=avio_rl32(s->pb);

            int pktct =avio_rl16(s->pb);

            int64_t pos      = s->data_offset + s->packet_size*(int64_t)pktnum;

            int64_t index_pts= av_rescale(itime, i, 10000);

            if(pos != last_pos){

            av_log(s, AV_LOG_DEBUG, "pktnum:%d, pktct:%d\n", pktnum, pktct);

            av_add_index_entry(s->streams[stream_index], pos, index_pts, s->packet_size, 0, AVINDEX_KEYFRAME);

            last_pos=pos;

            }

        }

        asf->index_read= 1;

    }

    avio_seek(s->pb, current_pos, SEEK_SET);

}

static int asf_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags)

{

    ASFContext *asf = s->priv_data;

    AVStream *st = s->streams[stream_index];

    int64_t pos;

    int index;

    if (s->packet_size <= 0)

        return -1;

    /* Try using the protocol's read_seek if available */

    if(s->pb) {

        int ret = av_url_read_fseek(s->pb, stream_index, pts, flags);

        if(ret >= 0)

            asf_reset_header(s);

        if (ret != AVERROR(ENOSYS))

            return ret;

    }

    if (!asf->index_read)

        asf_build_simple_index(s, stream_index);

    if(!(asf->index_read && st->index_entries)){

        if(av_seek_frame_binary(s, stream_index, pts, flags)<0)

            return -1;

    }else{

        index= av_index_search_timestamp(st, pts, flags);

        if(index<0)

            return -1;

        /* find the position */

        pos = st->index_entries[index].pos;

    // various attempts to find key frame have failed so far

    //    asf_reset_header(s);

    //    avio_seek(s->pb, pos, SEEK_SET);

    //    key_pos = pos;

    //     for(i=0;i<16;i++){

    //         pos = avio_tell(s->pb);

    //         if (av_read_frame(s, &pkt) < 0){

    //             av_log(s, AV_LOG_INFO, "seek failed\n");

    //             return -1;

    //         }

    //         asf_st = s->streams[stream_index]->priv_data;

    //         pos += st->parser->frame_offset;

    //

    //         if (pkt.size > b) {

    //             b = pkt.size;

    //             key_pos = pos;

    //         }

    //

    //         av_free_packet(&pkt);

    //     }

        /* do the seek */

        av_log(s, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos);

        avio_seek(s->pb, pos, SEEK_SET);

    }

    asf_reset_header(s);

    return 0;

}

AVInputFormat ff_asf_demuxer = {

    "asf",

    NULL_IF_CONFIG_SMALL("ASF format"),

    sizeof(ASFContext),

    asf_probe,

    asf_read_header,

    asf_read_packet,

    asf_read_close,

    asf_read_seek,

    asf_read_pts,

};