[FFmpeg-devel] [patch][GSoC]WTV muxer (2_wtvenc.patch, 3_add_wtv_muxer.patch)

Peter Ross pross at xvid.org
Sat Aug 20 17:20:49 CEST 2011


Hi. Comments against 2_wtvenc.patch and 3_add_wtv_muxer.patch

On Sun, Aug 14, 2011 at 09:07:59PM +0800, zhentan feng wrote:
> Hi,
> The attachment are 3 patches.
> #1 patch extracts common code from wtvdec.c and wtvenc.c to wtv.c and wtv.h
> #2 patch is the implementation wtvenc.c
> #3 patch integrates the muxer.

> diff --git a/libavformat/wtvenc.c b/libavformat/wtvenc.c
> new file mode 100644
> index 0000000..56c8baa
> --- /dev/null
> +++ b/libavformat/wtvenc.c
> @@ -0,0 +1,739 @@
> +/*
> + * Windows Television (WTV) muxer
> + * Copyright (c) 2011 Zhentan Feng <spyfeng at gmail dot com>
> + * Copyright (c) 2011 Peter Ross <pross at xvid.org>
> + * 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
> + */
> +
> +#include "libavutil/intreadwrite.h"
> +#include "avformat.h"
> +#include "internal.h"
> +#include "wtv.h"

> +
> +// ---
> +// FIXME: when stable, move this stuff to wtv.h
> +

Yhis comment is no longer needed

> +#define WTV_BIGSECTOR_SIZE (1 << WTV_BIGSECTOR_BITS)
> +#define INDEX_BASE 0x2
> +#define MAX_NB_INDEX 10
> +
> +/* declare utf16le strings */
> +#define _ , 0,
> +static const uint8_t timeline_table_0_header_events[] =
> +    {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e'_'.'_'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'h'_'e'_'a'_'d'_'e'_'r'_'.'_'E'_'v'_'e'_'n'_'t'_'s', 0};
> +static const uint8_t table_0_header_legacy_attrib[] =
> +    {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'h'_'e'_'a'_'d'_'e'_'r'_'.'_'l'_'e'_'g'_'a'_'c'_'y'_'_'_'a'_'t'_'t'_'r'_'i'_'b', 0};
> +static const uint8_t table_0_redirector_legacy_attrib[] =
> +    {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'r'_'e'_'d'_'i'_'r'_'e'_'c'_'t'_'o'_'r'_'.'_'l'_'e'_'g'_'a'_'c'_'y'_'_'_'a'_'t'_'t'_'r'_'i'_'b', 0};
> +static const uint8_t table_0_header_time[] =
> +    {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'h'_'e'_'a'_'d'_'e'_'r'_'.'_'t'_'i'_'m'_'e', 0};
> +static const uint8_t legacy_attrib[] =
> +    {'l'_'e'_'g'_'a'_'c'_'y'_'_'_'a'_'t'_'t'_'r'_'i'_'b', 0};
> +#undef _
> +
> +static const ff_asf_guid sub_wtv_guid =
> +    {0x8C,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
> +static const ff_asf_guid stream1_guid =
> +    {0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
> +static const ff_asf_guid sync_guid =
> +    {0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
> +static const ff_asf_guid index_guid =
> +    {0x96,0xc3,0xd2,0xc2,0x7e,0x9a,0xda,0x11,0x8b,0xf7,0x00,0x07,0xe9,0x5e,0xad,0x8d};
> +
> +enum WtvFileIndex {
> +    WTV_TIMELINE_TABLE_0_HEADER_EVENTS = 0,
> +    WTV_TIMELINE_TABLE_0_ENTRIES_EVENTS,
> +    WTV_TIMELINE,
> +    WTV_TABLE_0_HEADER_LEGACY_ATTRIB,
> +    WTV_TABLE_0_ENTRIES_LEGACY_ATTRIB,
> +    WTV_TABLE_0_REDIRECTOR_LEGACY_ATTRIB,
> +    WTV_TABLE_0_HEADER_TIME,
> +    WTV_TABLE_0_ENTRIES_TIME,
> +    WTV_FILES
> +};
> +
> +typedef struct {
> +    int64_t length;
> +    const void *header;
> +    int depth;
> +    int first_sector;
> +} WtvFile;
> +
> +typedef struct {
> +    int64_t             pos;
> +    int64_t             serial;
> +    const ff_asf_guid * guid;
> +    int                 stream_id;
> +} WtvChunkEntry;
> +
> +typedef struct {
> +    int64_t timeline_start_pos;
> +    WtvFile file[WTV_FILES];
> +    int64_t serial;          //chunk serial number
> +    int64_t last_chunk_pos;  // last chunk position
> +    int64_t frame_nb;
> +
> +    WtvChunkEntry index[MAX_NB_INDEX];
> +    int nb_index;
> +    int first_video_flag;
> +} WtvContext;
> +
> +typedef int WTVHeaderWriteFunc(AVIOContext *pb);
> +
> +typedef struct {
> +    const uint8_t *header;
> +    int header_size;
> +    WTVHeaderWriteFunc *write_header;
> +}WTVRootEntryTable;
> +
> +static int write_pad(AVIOContext *pb, int size)
> +{
> +    for (; size > 0; size--)
> +        avio_w8(pb, 0);
> +    return 0;
> +}
> +
> +static void put_guid(AVIOContext *s, const ff_asf_guid *g)
> +{
> +    assert(sizeof(*g) == 16);
> +    avio_write(s, *g, sizeof(*g));
> + }
> +
> +static const ff_asf_guid *get_codec_guid(enum CodecID id, const AVCodecGuid *av_guid)
> +{
> +    int i;
> +    for (i = 0; av_guid[i].id != CODEC_ID_NONE; i++) {
> +        if (id == av_guid[i].id)
> +            return &(av_guid[i].guid);
> +    }
> +    return NULL;
> +}
> +
> +/**
> + * Write chunk header. If header chunk (0x80000000 set) then add to list of header chunks
> + */
> +static void write_chunk_header(AVFormatContext *s, const ff_asf_guid *guid, int length, int stream_id)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    AVIOContext *pb = s->pb;
> +
> +    wctx->last_chunk_pos = avio_tell(pb) - wctx->timeline_start_pos;
> +    put_guid(pb, guid);
> +    avio_wl32(pb, 32 + length);
> +    avio_wl32(pb, stream_id);
> +    avio_wl64(pb, wctx->serial);
> +
> +    if ((stream_id & 0x80000000) && guid != &index_guid) {
> +        WtvChunkEntry *t = wctx->index + wctx->nb_index;
> +        t->pos       = wctx->last_chunk_pos;
> +        t->serial    = wctx->serial;
> +        t->guid      = guid;
> +        t->stream_id = stream_id & 0x3FFFFFFF;
> +        wctx->nb_index++;
> +    }
> +}
> +
> +static void write_chunk_header2(AVFormatContext *s, const ff_asf_guid *guid, int stream_id)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    AVIOContext *pb = s->pb;
> +
> +    int64_t last_chunk_pos = wctx->last_chunk_pos;
> +    write_chunk_header(s, guid, 0, stream_id); // lenth updated later
> +    avio_wl64(pb, last_chunk_pos);
> +}
> +
> +static void finish_chunk_noindex(AVFormatContext *s)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    AVIOContext *pb = s->pb;
> +
> +    // update the chunk_len field and pad.
> +    int64_t chunk_len = avio_tell(pb) - (wctx->last_chunk_pos + wctx->timeline_start_pos);
> +    avio_seek(pb, -(chunk_len - 16), SEEK_CUR);
> +    avio_wl32(pb, chunk_len);
> +    avio_seek(pb, chunk_len - (16 + 4), SEEK_CUR);
> +
> +    write_pad(pb, WTV_PAD8(chunk_len) - chunk_len);
> +    wctx->serial++;
> +}
> +
> +static void write_index(AVFormatContext *s)
> +{
> +    AVIOContext *pb = s->pb;
> +    WtvContext *wctx = s->priv_data;
> +    int i;
> +
> +    write_chunk_header2(s, &index_guid, 0x80000000);
> +    avio_wl32(pb, 0);
> +    avio_wl32(pb, 0);
> +
> +    for (i = 0; i < wctx->nb_index; i++) {
> +        WtvChunkEntry *t = wctx->index + i;
> +        put_guid(pb,  t->guid);
> +        avio_wl64(pb, t->pos);
> +        avio_wl32(pb, t->stream_id);
> +        avio_wl32(pb, 0); // checksum?
> +        avio_wl64(pb, t->serial);
> +    }
> +    wctx->nb_index = 0; // reset index
> +    finish_chunk_noindex(s);
> +}
> +
> +static void finish_chunk(AVFormatContext *s)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    finish_chunk_noindex(s);
> +    if (wctx->nb_index == MAX_NB_INDEX)
> +        write_index(s);
> +}
> +
> +static int write_stream_codec_info(AVFormatContext *s, AVStream *st)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    const ff_asf_guid *g, *media_type, *format_type;
> +    AVIOContext *pb = s->pb;
> +    int64_t  hdr_pos_start;
> +    int hdr_size = 0;
> +
> +    if (st->codec->codec_type  == AVMEDIA_TYPE_VIDEO) {
> +        g = get_codec_guid(st->codec->codec_id, ff_video_guids);
> +        media_type = &ff_mediatype_video;
> +        format_type = &format_mpeg2_video;
> +    } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
> +        g = get_codec_guid(st->codec->codec_id, ff_codec_wav_guids);
> +        media_type = &ff_mediatype_audio;
> +        format_type = &format_waveformatex;
> +    }  else {
> +        av_log(s, AV_LOG_ERROR, "unknown codec_type (0x%x)\n", st->codec->codec_type);
> +        return -1;
> +    }
> +
> +    if (g == NULL) {
> +        av_log(s, AV_LOG_ERROR, "can't get video codec_id (0x%x) guid.\n", st->codec->codec_id);
> +        return -1;
> +    }
> +
> +    put_guid(pb, media_type); // mediatype
> +    put_guid(pb, &mediasubtype_cpfilters_processed); // subtype
> +    write_pad(pb, 12);
> +    put_guid(pb,&format_cpfilters_processed); // format type
> +    avio_wl32(pb, 0); // size
> +    
     ^^
     trailing whitespace detected

> +    hdr_pos_start = avio_tell(pb);
> +    if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
> +        if (wctx->first_video_flag) {
> +            write_pad(pb, 216); //The size is sensitive.
> +            wctx->first_video_flag = 0;
> +        } else {
> +            write_pad(pb, 72); // aspect ratio
> +            ff_put_bmp_header(pb, st->codec, ff_codec_bmp_tags, 0);
> +        }
> +    } else {
> +        ff_put_wav_header(pb, st->codec);
> +    }
> +    hdr_size = avio_tell(pb) - hdr_pos_start;
> +   
     ^
     trailing whitespace detected. make sure these (and other instances) are removed in the next revision.

> +    // seek back write hdr_size
> +    avio_seek(pb, -(hdr_size + 4), SEEK_CUR);
> +    avio_wl32(pb, hdr_size + 32);
> +    avio_seek(pb, hdr_size, SEEK_CUR);
> +    put_guid(pb, g); // actual_subtype
> +    put_guid(pb, format_type); // actual_formattype
> +
> +    return 0;   
> +}
> +
> +static int write_stream_codec(AVFormatContext *s, AVStream * st)
> +{
> +    AVIOContext *pb = s->pb;
> +    int ret;
> +    write_chunk_header2(s, &stream1_guid, 0x80000000 | 0x01);
> +
> +    avio_wl32(pb,  0x01);
> +    write_pad(pb, 4);
> +    write_pad(pb, 4);
> +
> +    ret = write_stream_codec_info(s, st);
> +    if (ret < 0) {
> +        av_log(s, AV_LOG_ERROR, "write stream codec info failed codec_type(0x%x)\n", st->codec->codec_type);
> +        return -1;
> +    }
> +
> +    finish_chunk(s);
> +    return 0;
> +}
> +
> +static void write_sync(AVFormatContext *s)
> +{
> +    AVIOContext *pb = s->pb;
> +    WtvContext *wctx = s->priv_data;
> +    int64_t last_chunk_pos = wctx->last_chunk_pos;
> +
> +    write_chunk_header(s, &sync_guid, 0x18, 0);
> +    avio_wl64(pb, 0);  // FIXME: file-offset to previous keyframe
> +    avio_wl64(pb, -1); // FIXME: ??
> +    avio_wl64(pb, 0);  // FIXME: ??

Remove the 'FIXME: ??' comments. Like so much of the file format, these values are unknown.

> +
> +    finish_chunk(s);
> +
> +    wctx->last_chunk_pos = last_chunk_pos;
> +}
> +
> +static void write_DSATTRIB_TRANSPORT_PROPERTIES_init(AVFormatContext *s, int stream_index)
> +{
> +    AVIOContext *pb = s->pb;
> +    write_chunk_header2(s, &DSATTRIB_TRANSPORT_PROPERTIES, 0x80000000 | stream_index);
> +    avio_wl64(pb, stream_index);
> +    avio_wl64(pb, -1);
> +    avio_wl64(pb, 0);
> +    finish_chunk(s);
> +}
> +
> +static int write_stream_data(AVFormatContext *s, AVStream *st, int flag)
> +{
> +    AVIOContext *pb = s->pb;
> +    int ret;
> +    
> +    if (!flag) {
> +        write_chunk_header2(s, &ff_stream_guid, 0x80000000 | (st->index + INDEX_BASE));
> +        avio_wl32(pb, 0x00000001);
> +        avio_wl32(pb, st->index + INDEX_BASE); //stream_id
> +        avio_wl32(pb, 0x00000001);
> +        write_pad(pb, 8);
> +    } else {
> +        write_chunk_header2(s, &stream2_guid, 0x80000000 | (st->index + INDEX_BASE));
> +        write_pad(pb, 4);
> +    }
> +
> +    ret = write_stream_codec_info(s, st);
> +    if (ret < 0) {
> +        av_log(s, AV_LOG_ERROR, "write stream codec info failed codec_type(0x%x)\n", st->codec->codec_type);
> +        return -1;
> +    }
> +    finish_chunk(s);
> +
> +    av_set_pts_info(st, 64, 1, 10000000);
> +
> +    return 0;
> +}
> +
> +static int write_header(AVFormatContext *s)
> +{
> +    AVIOContext *pb = s->pb;
> +    WtvContext *wctx = s->priv_data;
> +    int i, pad;
> +    put_guid(pb, &ff_wtv_guid);
> +    put_guid(pb, &sub_wtv_guid);
> +
> +    avio_wl32(pb, 0x01);
> +    avio_wl32(pb, 0x02);
> +    avio_wl32(pb, 1 << WTV_SECTOR_BITS);
> +    avio_wl32(pb, 1 << WTV_BIGSECTOR_BITS);
> +
> +    //write initial root fields
> +    avio_wl32(pb, 0);  // root_size, update later

nit: why the double space before comment?

> +    write_pad(pb, 4);
> +    avio_wl32(pb, 0); // root_sector, update it later.
> +
> +    write_pad(pb, 32);
> +    avio_wl32(pb, 0); // file ends pointer, update it later. 
> +
> +    pad = (1 << WTV_SECTOR_BITS) - avio_tell(pb);
> +    write_pad(pb, pad);
> +    wctx->timeline_start_pos = avio_tell(pb);
> +
> +    wctx->serial = 1;
> +    wctx->last_chunk_pos = -1;
> +    wctx->first_video_flag = 1;
> +
> +    for (i = 0; i < s->nb_streams; i++) {
> +        int ret;

Consider declaring this at the top of the function.

> +        AVStream *st = s->streams[i];
> +        ret = write_stream_codec(s, st);
> +        if (ret < 0) {
> +            av_log(s, AV_LOG_ERROR, "write stream codec failed codec_type(0x%x)\n", st->codec->codec_type);
> +            return -1;
> +        }
> +        if (i + 1 < s->nb_streams) {
> +            write_sync(s);
> +        }
> +    }
> +
> +    for (i = 0; i < s->nb_streams; i++) {
> +        int ret;

Same.

> +        AVStream *st = s->streams[i];
> +        ret  = write_stream_data(s, st, 0);
> +        if (ret < 0) {
> +            av_log(s, AV_LOG_ERROR, "write stream data failed codec_type(0x%x)\n", st->codec->codec_type);
> +            return -1;
> +        }
> +        ret = write_stream_data(s, st, 1);
> +        if (ret < 0) {
> +            av_log(s, AV_LOG_ERROR, "write stream2 data failed codec_type(0x%x)\n", st->codec->codec_type);
> +            return -1;
> +        }
> +    }
> +
> +    for (i = 0; i < s->nb_streams; i++)
> +        write_DSATTRIB_TRANSPORT_PROPERTIES_init(s, INDEX_BASE + i);
> +
> +    if (wctx->nb_index)
> +        write_index(s);
> +
> +    return 0;
> +}
> +
> +static void write_timestamp(AVFormatContext *s, AVPacket *pkt)
> +{
> +    AVIOContext *pb = s->pb;
> +    WtvContext  *wctx = s->priv_data;
> +    AVCodecContext *enc = s->streams[pkt->stream_index]->codec;
> +    int flag = 0;
> +    int64_t frame_number = 0;
> +
> +    if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
> +        wctx->frame_nb++;
> +        frame_number = wctx->frame_nb;
> +        flag = pkt->flags & AV_PKT_FLAG_KEY ? 1 : 0;
> +    }
> +    write_chunk_header(s, &ff_timestamp_guid, 56, 0x40000000 | (INDEX_BASE + pkt->stream_index));
> +    write_pad(pb, 8);
> +    avio_wl64(pb, pkt->pts == AV_NOPTS_VALUE ? -1 : pkt->pts);
> +    avio_wl64(pb, pkt->pts == AV_NOPTS_VALUE ? -1 : pkt->pts);
> +
> +    avio_wl64(pb, frame_number);
> +    avio_wl64(pb, 0);
> +    avio_wl64(pb, flag);
> +    avio_wl64(pb, 0);
> +}
> +
> +static int write_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> +    AVIOContext *pb = s->pb;
> +    WtvContext  *wctx = s->priv_data;
> +
> +    // write timestamp chunk
> +    write_timestamp(s, pkt);
> +
> +    write_chunk_header(s, &ff_data_guid, pkt->size, INDEX_BASE + pkt->stream_index);
> +    avio_write(pb, pkt->data, pkt->size);
> +    write_pad(pb, WTV_PAD8(pkt->size) - pkt->size);
> +
> +    wctx->serial++;
> +    avio_flush(pb);
> +    return 0;
> +}
> +
> +static int write_table0_header_envents(AVIOContext *pb)
> +{
> +    avio_wl32(pb, 0x10);
> +    write_pad(pb, 84);
> +    avio_wl64(pb, 0x32);
> +    return 96;
> +}
> +
> +static int write_table0_header_legacy_attrib(AVIOContext *pb)
> +{
> +    int pad = 0;
> +    avio_wl32(pb, 0xFFFFFFFF);
> +    write_pad(pb, 12);
> +    avio_write(pb, legacy_attrib, sizeof(legacy_attrib));
> +    pad = WTV_PAD8(sizeof(legacy_attrib)) - sizeof(legacy_attrib);
> +    write_pad(pb, pad);
> +    write_pad(pb, 32);
> +    return 48 + WTV_PAD8(sizeof(legacy_attrib));
> +}
> +
> +static int write_table0_header_time(AVIOContext *pb)
> +{
> +    avio_wl32(pb, 0x10);
> +    write_pad(pb, 76);
> +    avio_wl64(pb, 0x40);
> +    return 88;
> +}
> +
> +static const WTVRootEntryTable wtv_root_entry_table[] = {
> +    { timeline_table_0_header_events, sizeof(timeline_table_0_header_events), write_table0_header_envents},
> +    { timeline_table_0_entries_Events_le16, sizeof(timeline_table_0_entries_Events_le16), NULL},
> +    { timeline_le16, sizeof(timeline_le16), NULL},
> +    { table_0_header_legacy_attrib, sizeof(table_0_header_legacy_attrib), write_table0_header_legacy_attrib},
> +    { table_0_entries_legacy_attrib_le16, sizeof(table_0_entries_legacy_attrib_le16), NULL},
> +    { table_0_redirector_legacy_attrib, sizeof(table_0_redirector_legacy_attrib), NULL},
> +    { table_0_header_time, sizeof(table_0_header_time), write_table0_header_time},
> +    { table_0_entries_time_le16, sizeof(table_0_entries_time_le16), NULL},
> +};

Consider using spaces to align the table columns.
   e.g.
    { timeline_table_0_header_events,       sizeof(timeline_table_0_header_events),       write_table0_header_envents},
    { timeline_table_0_entries_Events_le16, sizeof(timeline_table_0_entries_Events_le16), NULL},

> +
> +static int write_root_table(AVFormatContext *s, int64_t sector_pos)
> +{
> +    AVIOContext *pb = s->pb;
> +    WtvContext  *wctx = s->priv_data;
> +    int size, pad;
> +    int i;
> +
> +    const WTVRootEntryTable *h = wtv_root_entry_table;
> +    for (i = 0; i < sizeof(wtv_root_entry_table)/sizeof(WTVRootEntryTable); i++, h++) {
> +        WtvFile *w = &wctx->file[i];
> +        int filename_padding = WTV_PAD8(h->header_size) - h->header_size;
> +        WTVHeaderWriteFunc *write = h->write_header;
> +        int len = 0;
> +        int64_t len_pos;
> +
> +        put_guid(pb, &ff_dir_entry_guid);
> +        len_pos = avio_tell(pb);
> +        avio_wl16(pb, 40 + h->header_size + filename_padding + 8); // maybe updated later
> +        write_pad(pb, 6);
> +        avio_wl64(pb, write ? 0 : w->length);// maybe update later
> +        avio_wl32(pb, (h->header_size + filename_padding) >> 1);
> +        write_pad(pb, 4);
> +
> +        avio_write(pb, h->header, h->header_size);
> +        write_pad(pb, filename_padding);
> +
> +        if (write) {
> +            len = write(pb);
> +            // update length field
> +            avio_seek(pb, len_pos, SEEK_SET);
> +            avio_wl64(pb, 40 + h->header_size + filename_padding + len);
> +            avio_wl64(pb, len |(1ULL<<62) | (1ULL<<60));
> +            avio_seek(pb, 8 + h->header_size + filename_padding + len, SEEK_CUR);
> +        } else {
> +            avio_wl32(pb, w->first_sector);
> +            avio_wl32(pb, w->depth);
> +        }
> +    }
> +
> +    // caculate root table size
> +    size = avio_tell(pb) - sector_pos;
> +    pad = WTV_SECTOR_SIZE- size;
> +    write_pad(pb, pad);
> +
> +    return size;
> +}
> +
> +static void write_fat(AVIOContext *pb, int start_sector, int nb_sectors, int shift)
> +{
> +    int i;
> +    for (i = 0; i < nb_sectors; i++) {
> +        avio_wl32(pb, start_sector + (i << shift));
> +    }
> +    // pad left sector pointer size
> +    write_pad(pb, WTV_SECTOR_SIZE - (nb_sectors << 2));
> +}
> +
> +static int write_fat_sector(AVFormatContext *s, int64_t start_pos, int nb_sectors, int sector_bits, int depth)
> +{
> +    int64_t start_sector = start_pos >> WTV_SECTOR_BITS;
> +    int shift = sector_bits - WTV_SECTOR_BITS;
> +
> +    int64_t fat = avio_tell(s->pb);
> +    write_fat(s->pb, start_sector, nb_sectors, shift);
> +
> +    if (depth == 2) {
> +        int64_t start_sector1 = fat >> WTV_SECTOR_BITS;
> +        int nb_sectors1 = ((nb_sectors << 2) + WTV_SECTOR_SIZE - 1) / WTV_SECTOR_SIZE;
> +        int64_t fat1 = avio_tell(s->pb);
> +
> +       write_fat(s->pb, start_sector1, nb_sectors1, 0);
> +       return fat1;
> +    }
> +
> +    return fat;
> +}
> +
> +// table 2
> +static void write_table_entries_events(AVFormatContext *s)
> +{
> +    AVIOContext *pb = s->pb;
> +    //WtvContext *wctx = s->priv_data;
> +
> +    //FIXME: output frame_nb, position pairs
> +    //avio_wl64(pb, 0x2);   avio_wl64(pb, 0xc0);
> +    avio_wl64(pb, 0x2);   avio_wl64(pb, 0x170);

I thought this single-entry had to be present for WMC to playback the file _and_ that
it had to point to the a chunk.

0x170 is the file-offset (aka position) within the timeline file. 0x170 was just 
hard-coded for testing. Should this be caclulated from write_headers()?

> +    //avio_wl64(pb, 0x2);   avio_wl64(pb, 0x188);
> +}
> +
> +static void write_tag(AVIOContext *pb, const char *key, const char *value)
> +{
> +    put_guid(pb, &metadata_guid);
> +    avio_wl32(pb, 1);
> +    avio_wl32(pb, strlen(value)*2 + 2);
> +    avio_put_str16le(pb, key);
> +    avio_put_str16le(pb, value);
> +}
> +
> +static void write_table_entries_attrib(AVFormatContext *s)
> +{
> +    AVDictionaryEntry *tag = 0;
> +
> +    //FIXME: translate special tags (e.g. WM/Bitrate) to binary representation
> +    ff_metadata_conv(&s->metadata, ff_asf_metadata_conv, NULL);
> +    while((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX)))
> +        write_tag(s->pb, tag->key, tag->value);
> +}
> +
> +static void write_table_redirector_legacy_attrib(AVFormatContext *s)
> +{
> +    AVIOContext *pb = s->pb;
> +    AVDictionaryEntry *tag = 0;
> +    int64_t pos = 0;
> +
> +    //FIXME: translate special tags to binary representation
> +    while((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
> +        avio_wl64(pb, pos);
> +        pos += 16 + 4 + 4 + strlen(tag->key)*2 + 2 + strlen(tag->value)*2 + 2;
> +    }
> +}
> +
> +// table 7
> +// The content can be pad as zeroes because it is not necessary for playback.
> +static void write_table_entries_time(AVFormatContext *s)
> +{
> +    //AVIOContext *pb = s->pb;
> +    //WtvContext *wctx = s->priv_data;
> +
> +#if 0
> +    //avio_wl64(pb, 0x0);      avio_wl64(pb, 0x30);
> +    //avio_wl64(pb, 0x4c4b40); avio_wl64(pb, 0x43);
> +    //avio_wl64(pb, 0x7c8300); avio_wl64(pb, 0x50);
> +#else
> +    //FIXME: output timestamp, frame_nb pairs
> +#endif
> +}

If the muxer is not going to output timestmaps, then remove this placeholder function
and insert the FIXME down below where write_table_entries_time() is called.

> +
> +/**
> + * Pad the remainder of a file
> + * Write out fat table
> + * @return <0 on error
> + */
> +static int finish_file(AVFormatContext *s, enum WtvFileIndex index, int64_t start_pos)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    AVIOContext *pb = s->pb;
> +    WtvFile *w = &wctx->file[index];
> +    int64_t end_pos = avio_tell(pb);
> +    int sector_bits, nb_sectors, pad;
> +
> +    w->length = (end_pos - start_pos);
> +
> +    // determine optimal fat table depth, sector_bits, nb_sectors
> +    if (w->length <= WTV_SECTOR_SIZE) {
> +        w->depth = 0;
> +        sector_bits = WTV_SECTOR_BITS;
> +    } else if (w->length <= (WTV_SECTOR_SIZE / 4) * WTV_SECTOR_SIZE) {
> +        w->depth = 1;
> +        sector_bits = WTV_SECTOR_BITS;
> +    } else if (w->length <= (WTV_SECTOR_SIZE / 4) * WTV_BIGSECTOR_SIZE) {
> +        w->depth = 1;
> +        sector_bits = WTV_BIGSECTOR_BITS;
> +    } else if (w->length <= (int64_t)(WTV_SECTOR_SIZE / 4) * (WTV_SECTOR_SIZE / 4) * WTV_SECTOR_SIZE) {
> +        w->depth = 2;
> +        sector_bits = WTV_SECTOR_BITS;
> +    } else if (w->length <= (int64_t)(WTV_SECTOR_SIZE / 4) * (WTV_SECTOR_SIZE / 4) * WTV_BIGSECTOR_SIZE) {
> +        w->depth = 2;
> +        sector_bits = WTV_BIGSECTOR_BITS;
> +    } else {
> +        av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (%"PRIi64" bytes)\n", w->length);
> +        return -1;
> +    }
> +
> +    // determine the nb_sectors
> +    nb_sectors = (int)(w->length >> sector_bits);
> +
> +    // pad sector of timeline
> +    pad = (1 << sector_bits) - (w->length % (1 << sector_bits));
> +    if (pad) {
> +        nb_sectors++;
> +        write_pad(pb, pad);
> +    }
> +
> +    //write fat table
> +    if (w->depth > 0) {
> +        w->first_sector = write_fat_sector(s, start_pos, nb_sectors, sector_bits, w->depth);
> +    } else {
> +        w->first_sector = start_pos;
> +    }
> +    w->first_sector >>= WTV_SECTOR_BITS;
> +
> +    w->length |= 1ULL<<60;
> +    if (sector_bits == WTV_SECTOR_BITS)
> +        w->length |= 1ULL<<63;
> +
> +    return 0;
> +}
> +
> +static int write_trailer(AVFormatContext *s)
> +{
> +    WtvContext *wctx = s->priv_data;
> +    AVIOContext *pb = s->pb;
> +    int root_size;
> +    int64_t sector_pos;
> +    int64_t start_pos, file_end_pos;
> +
> +    if (finish_file(s, WTV_TIMELINE, wctx->timeline_start_pos) < 0)
> +        return -1;
> +
> +    start_pos = avio_tell(pb);
> +    write_table_entries_events(s);
> +    if (finish_file(s, WTV_TIMELINE_TABLE_0_ENTRIES_EVENTS, start_pos) < 0)
> +        return -1;
> +
> +    start_pos = avio_tell(pb);
> +    write_table_entries_attrib(s);
> +    if (finish_file(s, WTV_TABLE_0_ENTRIES_LEGACY_ATTRIB, start_pos) < 0)
> +        return -1;
> +
> +    start_pos = avio_tell(pb);
> +    write_table_redirector_legacy_attrib(s);
> +    if (finish_file(s, WTV_TABLE_0_REDIRECTOR_LEGACY_ATTRIB, start_pos) < 0)
> +        return -1;
> +
> +    start_pos = avio_tell(pb);
> +    write_table_entries_time(s);
> +    if (finish_file(s, WTV_TABLE_0_ENTRIES_TIME, start_pos) < 0)
> +        return -1;
> +
> +    // write root table
> +    sector_pos = avio_tell(pb);
> +    root_size = write_root_table(s, sector_pos);
> +
> +    file_end_pos = avio_tell(pb);
> +    // update root value
> +    avio_seek(pb, 0x30, SEEK_SET);
> +    avio_wl32(pb, root_size);
> +    avio_seek(pb, 4, SEEK_CUR);
> +    avio_wl32(pb, sector_pos >> WTV_SECTOR_BITS);
> +    avio_seek(pb, 0x5c, SEEK_SET);
> +    avio_wl32(pb, file_end_pos >> WTV_SECTOR_BITS);
> +
> +    avio_flush(pb);
> +    return 0;
> +}
> +
> +AVOutputFormat ff_wtv_muxer = {
> +    "wtv",
> +    NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
> +    NULL,
> +    "wtv",
> +    sizeof(WtvContext),
> +    CODEC_ID_MP2,
> +    CODEC_ID_MPEG2VIDEO,
> +    write_header,
> +    write_packet,
> +    write_trailer,
> +    .codec_tag= (const AVCodecTag* const []){ff_codec_bmp_tags, ff_codec_wav_tags, 0},
> +};

> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 9f5bfb4..a47e758 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -303,6 +303,7 @@ OBJS-$(CONFIG_WSAUD_DEMUXER)             += westwood.o
>  OBJS-$(CONFIG_WSVQA_DEMUXER)             += westwood.o
>  OBJS-$(CONFIG_WTV_DEMUXER)               += wtvdec.o wtv.o asfdec.o asf.o asfcrypt.o \
>                                              avlanguage.o mpegts.o isom.o riff.o
> +OBJS-$(CONFIG_WTV_MUXER)                 += wtvenc.o wtv.o asf.o riff.o
>  OBJS-$(CONFIG_WV_DEMUXER)                += wv.o apetag.o
>  OBJS-$(CONFIG_XA_DEMUXER)                += xa.o
>  OBJS-$(CONFIG_XWMA_DEMUXER)              += xwma.o riff.o
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index a9fa117..c11d744 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -224,7 +224,7 @@ void av_register_all(void)
>      REGISTER_MUXER    (WEBM, webm);
>      REGISTER_DEMUXER  (WSAUD, wsaud);
>      REGISTER_DEMUXER  (WSVQA, wsvqa);
> -    REGISTER_DEMUXER  (WTV, wtv);
> +    REGISTER_MUXDEMUX (WTV, wtv);    
>      REGISTER_DEMUXER  (WV, wv);
>      REGISTER_DEMUXER  (XA, xa);
>      REGISTER_DEMUXER  (XWMA, xwma);

Please go over the 'New codecs or formats checklist' in doc/developer.texi.
Your patch needs to update Changelog, doc/muxers.texi, etc.

Also patches 2 and 3 could probably be merged together to form a single 'WTV_muxer.patch'.

-- Peter
(A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
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