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

 * mpeg4video.c: mpeg 4 video packetizer

 *****************************************************************************

 * Copyright (C) 2001-2006 VLC authors and VideoLAN

 *

 * Authors: Gildas Bazin <gbazin@videolan.org>

 *          Laurent Aimar <fenrir@via.ecp.fr>

 *          Eric Petit <titer@videolan.org>

 *

 * This program 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.

 *

 * This program 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 this program; if not, write to the Free Software Foundation,

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

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

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

 * Preamble

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

#ifdef HAVE_CONFIG_H

# include "config.h"

#endif

#include <vlc_common.h>

#include <vlc_plugin.h>

#include <vlc_sout.h>

#include <vlc_codec.h>

#include <vlc_block.h>

#include <vlc_bits.h>

#include <vlc_block_helper.h>

#include "packetizer_helper.h"

#include "startcode_helper.h"

#include "h26x_nal_common.h"

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

 * Module descriptor

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

static int  Open ( vlc_object_t * );

static void Close( vlc_object_t * );

vlc_module_begin ()

    set_subcategory( SUBCAT_SOUT_PACKETIZER )

    set_description( N_("MPEG4 video packetizer") )

    set_capability( "video packetizer", 50 )

    set_callbacks( Open, Close )

vlc_module_end ()

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

 * Local prototypes

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

typedef struct

{

    /*

     * Input properties

     */

    packetizer_t packetizer;

    /*

     * Common properties

     */

    vlc_tick_t i_interpolated_pts;

    vlc_tick_t i_interpolated_dts;

    vlc_tick_t i_last_ref_pts;

    uint64_t i_last_time_ref;

    uint64_t i_time_ref;

    int64_t i_last_time;

    uint32_t i_last_timeincr;

    unsigned int i_flags;

    uint16_t    i_fps_num;

    bool  b_frame;

    /* Current frame being built */

    block_t    *p_frame;

    block_t    **pp_last;

} decoder_sys_t;

static block_t *Packetize( decoder_t *, block_t ** );

static void PacketizeFlush( decoder_t * );

static void PacketizeReset( void *p_private, bool b_broken );

static block_t *PacketizeParse( void *p_private, bool *pb_ts_used, block_t * );

static int PacketizeValidate( void *p_private, block_t * );

static block_t *ParseMPEGBlock( decoder_t *, block_t * );

static int ParseVOL( decoder_t *, es_format_t *, uint8_t *, int );

static int ParseVO( decoder_t *, block_t * );

static int ParseVOP( decoder_t *, block_t * );

#define VIDEO_OBJECT_MASK                       0x01f

#define VIDEO_OBJECT_LAYER_MASK                 0x00f

#define VIDEO_OBJECT_START_CODE                 0x100

#define VIDEO_OBJECT_LAYER_START_CODE           0x120

#define RESERVED_START_CODE                     0x130

#define VISUAL_OBJECT_SEQUENCE_START_CODE       0x1b0

#define VISUAL_OBJECT_SEQUENCE_END_CODE         0x1b1

#define USER_DATA_START_CODE                    0x1b2

#define GROUP_OF_VOP_START_CODE                 0x1b3

#define VIDEO_SESSION_ERROR_CODE                0x1b4

#define VISUAL_OBJECT_START_CODE                0x1b5

#define VOP_START_CODE                          0x1b6

#define FACE_OBJECT_START_CODE                  0x1ba

#define FACE_OBJECT_PLANE_START_CODE            0x1bb

#define MESH_OBJECT_START_CODE                  0x1bc

#define MESH_OBJECT_PLANE_START_CODE            0x1bd

#define STILL_TEXTURE_OBJECT_START_CODE         0x1be

#define TEXTURE_SPATIAL_LAYER_START_CODE        0x1bf

#define TEXTURE_SNR_LAYER_START_CODE            0x1c0

static const uint8_t p_mp4v_startcode[3] = { 0x00, 0x00, 0x01 };

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

 * Open: probe the packetizer and return score

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

static int Open( vlc_object_t *p_this )

{

    decoder_t     *p_dec = (decoder_t*)p_this;

    decoder_sys_t *p_sys;

    if( p_dec->fmt_in->i_codec != VLC_CODEC_MP4V )

        return VLC_EGENERIC;

    /* Allocate the memory needed to store the decoder's structure */

    if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )

        return VLC_ENOMEM;

    memset( p_sys, 0, sizeof(decoder_sys_t) );

    /* Misc init */

    packetizer_Init( &p_sys->packetizer,

                     p_mp4v_startcode, sizeof(p_mp4v_startcode), startcode_FindAnnexB,

                     NULL, 0, 4,

                     PacketizeReset, PacketizeParse, PacketizeValidate, NULL,

                     p_dec );

    p_sys->p_frame = NULL;

    p_sys->pp_last = &p_sys->p_frame;

    /* Setup properties */

    es_format_Copy( &p_dec->fmt_out, p_dec->fmt_in );

    p_dec->fmt_out.i_codec = VLC_CODEC_MP4V;

    if( p_dec->fmt_out.i_extra )

    {

        /* We have a vol */

        msg_Dbg( p_dec, "opening with vol size: %zu", p_dec->fmt_out.i_extra );

        ParseVOL( p_dec, &p_dec->fmt_out,

                  p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );

    }

    /* Set callback */

    p_dec->pf_packetize = Packetize;

    p_dec->pf_flush = PacketizeFlush;

    p_dec->pf_get_cc = NULL;

    return VLC_SUCCESS;

}

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

 * Close: clean up the packetizer

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

static void Close( vlc_object_t *p_this )

{

    decoder_t *p_dec = (decoder_t*)p_this;

    decoder_sys_t *p_sys = p_dec->p_sys;

    packetizer_Clean( &p_sys->packetizer );

    if( p_sys->p_frame )

        block_ChainRelease( p_sys->p_frame );

    free( p_sys );

}

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

 * Packetize: the whole thing

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

static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )

{

    decoder_sys_t *p_sys = p_dec->p_sys;

    return packetizer_Packetize( &p_sys->packetizer, pp_block );

}

static void PacketizeFlush( decoder_t *p_dec )

{

    decoder_sys_t *p_sys = p_dec->p_sys;

    packetizer_Flush( &p_sys->packetizer );

}

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

 * Helpers:

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

static void PacketizeReset( void *p_private, bool b_flush )

{

    decoder_t *p_dec = p_private;

    decoder_sys_t *p_sys = p_dec->p_sys;

    if( b_flush )

    {

        if( p_sys->p_frame )

            block_ChainRelease( p_sys->p_frame );

        p_sys->p_frame = NULL;

        p_sys->pp_last = &p_sys->p_frame;

    }

    p_sys->i_interpolated_pts =

    p_sys->i_interpolated_dts =

    p_sys->i_last_ref_pts = VLC_TICK_INVALID;

    p_sys->i_last_time_ref =

    p_sys->i_time_ref =

    p_sys->i_last_time =

    p_sys->i_last_timeincr = 0;

}

static block_t *PacketizeParse( void *p_private, bool *pb_ts_used, block_t *p_block )

{

    decoder_t *p_dec = p_private;

    const vlc_tick_t i_dts = p_block->i_dts;

    const vlc_tick_t i_pts = p_block->i_pts;

    block_t *p_au = ParseMPEGBlock( p_dec, p_block );

    *pb_ts_used = p_au &&  p_au->i_dts == i_dts && p_au->i_pts == i_pts;

    return p_au;

}

static int PacketizeValidate( void *p_private, block_t *p_au )

{

    decoder_t *p_dec = p_private;

    decoder_sys_t *p_sys = p_dec->p_sys;

    /* We've just started the stream, wait for the first PTS.

     * We discard here so we can still get the sequence header. */

    if( p_sys->i_interpolated_pts == VLC_TICK_INVALID &&

        p_sys->i_interpolated_dts == VLC_TICK_INVALID )

    {

        msg_Dbg( p_dec, "need a starting pts/dts" );

        return VLC_EGENERIC;

    }

    /* When starting the stream we can have the first frame with

     * a null DTS (i_interpolated_pts is initialized to 0) */

    if( p_au->i_dts == VLC_TICK_INVALID )

        p_au->i_dts = p_au->i_pts;

    return VLC_SUCCESS;

}

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

 * ParseMPEGBlock: Re-assemble fragments into a block containing a picture

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

static block_t *ParseMPEGBlock( decoder_t *p_dec, block_t *p_frag )

{

    decoder_sys_t *p_sys = p_dec->p_sys;

    block_t *p_pic = NULL;

    if( p_frag->i_buffer < 4 )

        return p_frag;

    const uint32_t i_startcode = GetDWBE( p_frag->p_buffer );

    if( i_startcode == VISUAL_OBJECT_SEQUENCE_START_CODE ||

        i_startcode == VISUAL_OBJECT_SEQUENCE_END_CODE ||

        i_startcode == USER_DATA_START_CODE )

    {   /* VOS and USERDATA */

#if 0

        /* Remove VOS start/end code from the original stream */

        block_Release( p_frag );

#else

        /* Append the block for now since ts/ps muxers rely on VOL

         * being present in the stream */

        block_ChainLastAppend( &p_sys->pp_last, p_frag );

#endif

        return NULL;

    }

    else if( i_startcode >= VIDEO_OBJECT_LAYER_START_CODE &&

             i_startcode < RESERVED_START_CODE )

    {

        /* Copy the complete VOL */

        if( (size_t)p_dec->fmt_out.i_extra != p_frag->i_buffer ||

           ( p_frag->i_buffer && memcmp(p_dec->fmt_out.p_extra,

                                        p_frag->p_buffer, p_frag->i_buffer) ) )

        {

            void *p_realloc = realloc( p_dec->fmt_out.p_extra, p_frag->i_buffer );

            if( p_realloc )

            {

                p_dec->fmt_out.p_extra = p_realloc;

                p_dec->fmt_out.i_extra = p_frag->i_buffer;

                memcpy( p_realloc, p_frag->p_buffer, p_frag->i_buffer );

            }

        }

        ParseVOL( p_dec, &p_dec->fmt_out,

                  p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );

#if 0

        /* Remove from the original stream */

        block_Release( p_frag );

#else

        /* Append the block for now since ts/ps muxers rely on VOL

         * being present in the stream */

        block_ChainLastAppend( &p_sys->pp_last, p_frag );

#endif

        return NULL;

    }

    else

    {

        if( !p_dec->fmt_out.i_extra )

        {

            msg_Warn( p_dec, "waiting for VOL" );

            block_Release( p_frag );

            return NULL;

        }

        /* Append the block */

        block_ChainLastAppend( &p_sys->pp_last, p_frag );

    }

    if( i_startcode == VISUAL_OBJECT_START_CODE )

    {

        ParseVO( p_dec, p_frag );

    }

    else

    if( i_startcode == VOP_START_CODE &&

        ParseVOP( p_dec, p_frag ) == VLC_SUCCESS )

    {

        /* We are dealing with a VOP */

        p_pic = block_ChainGather( p_sys->p_frame );

        p_pic->i_flags = p_sys->i_flags;

        p_pic->i_pts = p_sys->i_interpolated_pts;

        p_pic->i_dts = p_sys->i_interpolated_dts;

#if 0

    msg_Err( p_dec, "output dts/pts (%"PRId64",%"PRId64")", p_pic->i_dts, p_pic->i_pts );

#endif

        /* Reset context */

        p_sys->p_frame = NULL;

        p_sys->pp_last = &p_sys->p_frame;

    }

    return p_pic;

}

/* ParseVOL: */

static int ParseVOL( decoder_t *p_dec, es_format_t *fmt,

                     uint8_t *p_vol, int i_vol )

{

    decoder_sys_t *p_sys = p_dec->p_sys;

    int i_vo_ver_id, i_shape;

    h26x_aspect_ratio_t ar;

    bs_t s;

    for( ;; )

    {

        if( i_vol <= 5 )

            return VLC_EGENERIC;

        uint32_t i_startcode = GetDWBE( p_vol );

        if( i_startcode >= VIDEO_OBJECT_LAYER_START_CODE &&

            i_startcode < RESERVED_START_CODE )

            break;

        p_vol++; i_vol--;

    }

    bs_init( &s, &p_vol[4], i_vol - 4 );

    bs_skip( &s, 1 );   /* random access */

    bs_skip( &s, 8 );   /* vo_type */

    if( bs_read1( &s ) )

    {

        i_vo_ver_id = bs_read( &s, 4 );

        bs_skip( &s, 3 );

    }

    else

    {

        i_vo_ver_id = 1;

    }

    ar.aspect_ratio_idc = bs_read( &s, 4 ) & 0xf;

    if( ar.aspect_ratio_idc == 0xf )

    {

        ar.aspect_ratio_idc = 0xff; // was only coded on 4 bits in MPEG4

        ar.sar_width = bs_read( &s, 8 );

        ar.sar_height = bs_read( &s, 8 );

    }

    if(!p_dec->fmt_in->video.i_sar_num ||

       !p_dec->fmt_in->video.i_sar_den)

    {

        h26x_get_aspect_ratio(&ar,

                              &fmt->video.i_sar_num,

                              &fmt->video.i_sar_den);

    }

    if( bs_read1( &s ) )

    {

        /* vol control parameter */

        bs_skip( &s, 2 ); /* chroma_format */

        bs_skip( &s, 1 ); /* low_delay */

        if( bs_read1( &s ) )

        {

            bs_skip( &s, 16 );

            bs_skip( &s, 16 );

            bs_skip( &s, 16 );

            bs_skip( &s, 3 );

            bs_skip( &s, 11 );

            bs_skip( &s, 1 );

            bs_skip( &s, 16 );

        }

    }

    /* shape 0->RECT, 1->BIN, 2->BIN_ONLY, 3->GRAY */

    i_shape = bs_read( &s, 2 );

    if( i_shape == 3 && i_vo_ver_id != 1 )

    {

        bs_skip( &s, 4 );

    }

    if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */

    p_sys->i_fps_num = bs_read( &s, 16 ); /* Time increment resolution*/

    if( !p_sys->i_fps_num ) p_sys->i_fps_num = 1;

    if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */

    if( bs_read1( &s ) )

    {

        unsigned i_time_increment_bits = vlc_log2( p_sys->i_fps_num - 1 ) + 1;

        bs_skip( &s, i_time_increment_bits ); /* i_fps_den */

    }

    if( i_shape == 0 )

    {

        bs_skip( &s, 1 );

        fmt->video.i_width = bs_read( &s, 13 );

        bs_skip( &s, 1 );

        fmt->video.i_height= bs_read( &s, 13 );

        bs_skip( &s, 1 );

    }

    return VLC_SUCCESS;

}

static int ParseVO( decoder_t *p_dec, block_t *p_vo )

{

    bs_t s;

    bs_init( &s, &p_vo->p_buffer[4], p_vo->i_buffer - 4 );

    if( bs_read1( &s ) )

        bs_skip( &s, 7 );

    const uint8_t visual_object_type = bs_read( &s, 4 );

    if( visual_object_type == 1 /* video ID */ ||

        visual_object_type == 2 /* still texture ID */ )

    {

        h26x_colour_description_t colour =

        {

            .colour_primaries = 1,

            .transfer_characteristics = 1,

            .matrix_coeffs = 1,

            .full_range_flag = 0,

        };

        if( bs_read1( &s ) ) /* video_signal_type */

        {

            bs_skip( &s, 3 );

            colour.full_range_flag = bs_read( &s, 1 );

            if( bs_read( &s, 1 ) ) /* colour description */

            {

                colour.colour_primaries = bs_read( &s, 8 );

                colour.transfer_characteristics = bs_read( &s, 8 );

                colour.matrix_coeffs = bs_read( &s, 8 );

            }

        }

        if( p_dec->fmt_in->video.primaries == COLOR_PRIMARIES_UNDEF )

        {

            h26x_get_colorimetry( &colour,

                                  &p_dec->fmt_out.video.primaries,

                                  &p_dec->fmt_out.video.transfer,

                                  &p_dec->fmt_out.video.space,

                                  &p_dec->fmt_out.video.color_range );

        }

    }

    return VLC_SUCCESS;

}

static int ParseVOP( decoder_t *p_dec, block_t *p_vop )

{

    decoder_sys_t *p_sys = p_dec->p_sys;

    uint64_t i_time_ref;

    uint32_t i_time_increment;

    uint64_t i_modulo_time_base = 0;

    bs_t s;

    bs_init( &s, &p_vop->p_buffer[4], p_vop->i_buffer - 4 );

    switch( bs_read( &s, 2 ) )

    {

    case 0:

        p_sys->i_flags = BLOCK_FLAG_TYPE_I;

        break;

    case 1:

        p_sys->i_flags = BLOCK_FLAG_TYPE_P;

        break;

    case 2:

        p_sys->i_flags = BLOCK_FLAG_TYPE_B;

        p_sys->b_frame = true;

        break;

    case 3: /* Sprite : ISO 14496-2 § 6.3.5 */

        p_sys->i_flags = BLOCK_FLAG_TYPE_PB;

        break;

    }

    while( bs_read( &s, 1 ) ) i_modulo_time_base++;

    if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */

    /* Interpolate PTS/DTS */

    if( !(p_sys->i_flags & BLOCK_FLAG_TYPE_B) )

    {

        p_sys->i_last_time_ref = p_sys->i_time_ref;

        p_sys->i_time_ref +=

            (i_modulo_time_base * p_sys->i_fps_num);

        i_time_ref = p_sys->i_time_ref;

    }

    else

    {

        i_time_ref = p_sys->i_last_time_ref +

            (i_modulo_time_base * p_sys->i_fps_num);

    }

    if( p_sys->i_fps_num )

    {

        /* VOP time increment */

        unsigned i_time_increment_bits = vlc_log2(p_sys->i_fps_num - 1) + 1;

        i_time_increment = bs_read( &s, i_time_increment_bits );

        int64_t i_time_diff = (i_time_ref + i_time_increment) - (p_sys->i_last_time + p_sys->i_last_timeincr);

        if( i_modulo_time_base == 0 && i_time_diff < 0 && -i_time_diff > p_sys->i_fps_num )

        {

            msg_Warn(p_dec, "missing modulo_time_base update");

            i_modulo_time_base += -i_time_diff / p_sys->i_fps_num;

            p_sys->i_time_ref += (i_modulo_time_base * p_sys->i_fps_num);

            p_sys->i_time_ref += p_sys->i_last_timeincr % p_sys->i_fps_num;

            i_time_ref = p_sys->i_time_ref;

        }

    }

    if( p_sys->i_fps_num < 5 && /* Work-around buggy streams */

        p_dec->fmt_in->video.i_frame_rate > 0 &&

        p_dec->fmt_in->video.i_frame_rate_base > 0 )

    {

        p_sys->i_interpolated_pts += vlc_tick_from_samples(

        p_dec->fmt_in->video.i_frame_rate_base,

        p_dec->fmt_in->video.i_frame_rate);

    }

    else

    {

        int64_t i_time_diff = (i_time_ref + i_time_increment) - (p_sys->i_last_time + p_sys->i_last_timeincr);

        p_sys->i_interpolated_pts += vlc_tick_from_samples( i_time_diff, p_sys->i_fps_num );

    }

#if 0

    msg_Err( p_dec, "interp dts/pts (%"PRId64",%"PRId64"), dts/pts (%"PRId64",%"PRId64") %"PRId64" mod %d inc %"PRId64,

             p_sys->i_interpolated_dts, p_sys->i_interpolated_pts,

             p_vop->i_dts, p_vop->i_pts, p_sys->i_time_ref, i_modulo_time_base, i_time_increment );

#endif

    p_sys->i_last_time = i_time_ref;

    if( p_sys->i_fps_num )

        p_sys->i_last_timeincr = i_time_increment;

    /* Correct interpolated dts when we receive a new pts/dts */

    if( p_vop->i_pts != VLC_TICK_INVALID )

        p_sys->i_interpolated_pts = p_vop->i_pts;

    if( p_vop->i_dts != VLC_TICK_INVALID )

        p_sys->i_interpolated_dts = p_vop->i_dts;

    if( (p_sys->i_flags & BLOCK_FLAG_TYPE_B) || !p_sys->b_frame )

    {

        /* Trivial case (DTS == PTS) */

        p_sys->i_interpolated_dts = p_sys->i_interpolated_pts;

        if( p_vop->i_pts != VLC_TICK_INVALID )

            p_sys->i_interpolated_dts = p_vop->i_pts;

        if( p_vop->i_dts != VLC_TICK_INVALID )

            p_sys->i_interpolated_dts = p_vop->i_dts;

        p_sys->i_interpolated_pts = p_sys->i_interpolated_dts;

    }

    else

    {

        if( p_sys->i_last_ref_pts != VLC_TICK_INVALID )

            p_sys->i_interpolated_dts = p_sys->i_last_ref_pts;

        p_sys->i_last_ref_pts = p_sys->i_interpolated_pts;

    }

    return VLC_SUCCESS;

}