video.c

video linux conference

/*****************************************************************************
 * video.c: video decoder using the ffmpeg library
 *****************************************************************************
 * Copyright (C) 1999-2001 VideoLAN
 * $Id: video.c 11515 2005-06-24 20:39:26Z gbazin $
 *
 * Authors: Laurent Aimar <[e-mail]>
 *          Gildas Bazin <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <vlc/vlc.h>
#include <vlc/decoder.h>
#include <vlc/input.h>                  /* hmmm, just for INPUT_RATE_DEFAULT */

/* ffmpeg header */
#ifdef HAVE_FFMPEG_AVCODEC_H
#   include <ffmpeg/avcodec.h>
#else
#   include <avcodec.h>
#endif

#include "ffmpeg.h"

/*****************************************************************************
 * decoder_sys_t : decoder descriptor
 *****************************************************************************/
struct decoder_sys_t
{
    /* Common part between video and audio decoder */
    int i_cat;
    int i_codec_id;
    char *psz_namecodec;

    AVCodecContext      *p_context;
    AVCodec             *p_codec;

    /* Video decoder specific part */
    mtime_t input_pts;
    mtime_t input_dts;
    mtime_t i_pts;

    AVFrame          *p_ff_pic;
    BITMAPINFOHEADER *p_format;

    /* for frame skipping algo */
    int b_hurry_up;
    int i_frame_skip;

    /* how many decoded frames are late */
    int     i_late_frames;
    mtime_t i_late_frames_start;

    /* for direct rendering */
    int b_direct_rendering;

    vlc_bool_t b_has_b_frames;

    /* Hack to force display of still pictures */
    vlc_bool_t b_first_frame;

    int i_buffer_orig, i_buffer;
    char *p_buffer_orig, *p_buffer;

    /* Postprocessing handle */
    void *p_pp;
    vlc_bool_t b_pp;
    vlc_bool_t b_pp_async;
    vlc_bool_t b_pp_init;
};

/* FIXME (dummy palette for now) */
static AVPaletteControl palette_control;

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static void ffmpeg_InitCodec      ( decoder_t * );
static void ffmpeg_CopyPicture    ( decoder_t *, picture_t *, AVFrame * );
static int  ffmpeg_GetFrameBuf    ( struct AVCodecContext *, AVFrame * );
static void ffmpeg_ReleaseFrameBuf( struct AVCodecContext *, AVFrame * );

static uint32_t ffmpeg_CodecTag( vlc_fourcc_t fcc )
{
    uint8_t *p = (uint8_t*)&fcc;
    return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
}

/*****************************************************************************
 * Local Functions
 *****************************************************************************/
static uint32_t ffmpeg_PixFmtToChroma( int i_ff_chroma )
{
    switch( i_ff_chroma )
    {
    case PIX_FMT_YUV420P:
    case PIX_FMT_YUVJ420P: /* Hacky but better then chroma conversion */
        return VLC_FOURCC('I','4','2','0');
    case PIX_FMT_YUV422P:
    case PIX_FMT_YUVJ422P: /* Hacky but better then chroma conversion */
        return VLC_FOURCC('I','4','2','2');
    case PIX_FMT_YUV444P:
    case PIX_FMT_YUVJ444P: /* Hacky but better then chroma conversion */
        return VLC_FOURCC('I','4','4','4');

    case PIX_FMT_YUV422:
        return VLC_FOURCC('Y','U','Y','2');

    case PIX_FMT_RGB555:
        return VLC_FOURCC('R','V','1','5');
    case PIX_FMT_RGB565:
        return VLC_FOURCC('R','V','1','6');
    case PIX_FMT_RGB24:
        return VLC_FOURCC('R','V','2','4');
    case PIX_FMT_RGBA32:
        return VLC_FOURCC('R','V','3','2');
    case PIX_FMT_GRAY8:
        return VLC_FOURCC('G','R','E','Y');

    case PIX_FMT_YUV410P:
    case PIX_FMT_YUV411P:
    case PIX_FMT_BGR24:
    default:
        return 0;
    }
}

/* Returns a new picture buffer */
static inline picture_t *ffmpeg_NewPictBuf( decoder_t *p_dec,
                                            AVCodecContext *p_context )
{
    decoder_sys_t *p_sys = p_dec->p_sys;
    picture_t *p_pic;

    p_dec->fmt_out.video.i_width = p_context->width;
    p_dec->fmt_out.video.i_height = p_context->height;
    p_dec->fmt_out.i_codec = ffmpeg_PixFmtToChroma( p_context->pix_fmt );

    if( !p_context->width || !p_context->height )
    {
        return NULL; /* invalid display size */
    }

    if( !p_dec->fmt_out.i_codec )
    {
        /* we make conversion if possible*/
        p_dec->fmt_out.i_codec = VLC_FOURCC('I','4','2','0');
    }

    /* If an aspect-ratio was specified in the input format then force it */
    if( p_dec->fmt_in.video.i_aspect )
    {
        p_dec->fmt_out.video.i_aspect = p_dec->fmt_in.video.i_aspect;
    }
    else
    {
#if LIBAVCODEC_BUILD >= 4687
        p_dec->fmt_out.video.i_aspect =
            VOUT_ASPECT_FACTOR * ( av_q2d(p_context->sample_aspect_ratio) *
                p_context->width / p_context->height );
        p_dec->fmt_out.video.i_sar_num = p_context->sample_aspect_ratio.num;
        p_dec->fmt_out.video.i_sar_den = p_context->sample_aspect_ratio.den;
#else
        p_dec->fmt_out.video.i_aspect =
            VOUT_ASPECT_FACTOR * p_context->aspect_ratio;
#endif
        if( p_dec->fmt_out.video.i_aspect == 0 )
        {
            p_dec->fmt_out.video.i_aspect =
                VOUT_ASPECT_FACTOR * p_context->width / p_context->height;
        }
    }

#if LIBAVCODEC_BUILD >= 4754
    if( p_context->time_base.num > 0 && p_context->time_base.den > 0 )
    {
        p_dec->fmt_out.video.i_frame_rate = p_context->time_base.den;
        p_dec->fmt_out.video.i_frame_rate_base = p_context->time_base.num;
    }
#else
    if( p_context->frame_rate > 0 && p_context->frame_rate_base > 0 )
    {
        p_dec->fmt_out.video.i_frame_rate = p_context->frame_rate;
        p_dec->fmt_out.video.i_frame_rate_base = p_context->frame_rate_base;
    }
#endif

    p_pic = p_dec->pf_vout_buffer_new( p_dec );

#ifdef LIBAVCODEC_PP
    if( p_sys->p_pp && p_sys->b_pp && !p_sys->b_pp_init )
    {
        E_(InitPostproc)( p_dec, p_sys->p_pp, p_context->width,
                          p_context->height, p_context->pix_fmt );
        p_sys->b_pp_init = VLC_TRUE;
    }
#endif

    return p_pic;
}

/*****************************************************************************
 * InitVideo: initialize the video decoder
 *****************************************************************************
 * the ffmpeg codec will be opened, some memory allocated. The vout is not yet
 * opened (done after the first decoded frame).
 *****************************************************************************/
int E_(InitVideoDec)( decoder_t *p_dec, AVCodecContext *p_context,
                      AVCodec *p_codec, int i_codec_id, char *psz_namecodec )
{
    decoder_sys_t *p_sys;
    vlc_value_t lockval;
    vlc_value_t val;

    var_Get( p_dec->p_libvlc, "avcodec", &lockval );

    /* Allocate the memory needed to store the decoder's structure */
    if( ( p_dec->p_sys = p_sys =
          (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
    {
        msg_Err( p_dec, "out of memory" );
        return VLC_EGENERIC;
    }

    p_dec->p_sys->p_context = p_context;
    p_dec->p_sys->p_codec = p_codec;
    p_dec->p_sys->i_codec_id = i_codec_id;
    p_dec->p_sys->psz_namecodec = psz_namecodec;
    p_sys->p_ff_pic = avcodec_alloc_frame();

    /* ***** Fill p_context with init values ***** */
    /* FIXME: remove when ffmpeg deals properly with avc1 */
    if( p_dec->fmt_in.i_codec != VLC_FOURCC('a','v','c','1') )
    /* End FIXME */
    p_sys->p_context->codec_tag = ffmpeg_CodecTag( p_dec->fmt_in.i_codec );
    p_sys->p_context->width  = p_dec->fmt_in.video.i_width;
    p_sys->p_context->height = p_dec->fmt_in.video.i_height;
    p_sys->p_context->bits_per_sample = p_dec->fmt_in.video.i_bits_per_pixel;

    /*  ***** Get configuration of ffmpeg plugin ***** */
    p_sys->p_context->workaround_bugs =
        config_GetInt( p_dec, "ffmpeg-workaround-bugs" );
    p_sys->p_context->error_resilience =
        config_GetInt( p_dec, "ffmpeg-error-resilience" );

    var_Create( p_dec, "grayscale", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
    var_Get( p_dec, "grayscale", &val );
    if( val.b_bool ) p_sys->p_context->flags |= CODEC_FLAG_GRAY;

    var_Create( p_dec, "ffmpeg-vismv", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
    var_Get( p_dec, "ffmpeg-vismv", &val );
#if LIBAVCODEC_BUILD >= 4698
    if( val.i_int ) p_sys->p_context->debug_mv = val.i_int;
#endif

    var_Create( p_dec, "ffmpeg-lowres", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
    var_Get( p_dec, "ffmpeg-lowres", &val );
#if LIBAVCODEC_BUILD >= 4723
    if( val.i_int > 0 && val.i_int <= 2 ) p_sys->p_context->lowres = val.i_int;
#endif

    /* ***** ffmpeg frame skipping ***** */
    var_Create( p_dec, "ffmpeg-hurry-up", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
    var_Get( p_dec, "ffmpeg-hurry-up", &val );
    p_sys->b_hurry_up = val.b_bool;

    /* ***** ffmpeg direct rendering ***** */
    p_sys->b_direct_rendering = 0;
    var_Create( p_dec, "ffmpeg-dr", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
    var_Get( p_dec, "ffmpeg-dr", &val );
    if( val.b_bool && (p_sys->p_codec->capabilities & CODEC_CAP_DR1) &&
        ffmpeg_PixFmtToChroma( p_sys->p_context->pix_fmt ) &&
        /* Apparently direct rendering doesn't work with YUV422P */
        p_sys->p_context->pix_fmt != PIX_FMT_YUV422P &&
        /* H264 uses too many reference frames */
        p_sys->i_codec_id != CODEC_ID_H264 &&
        !(p_sys->p_context->width % 16) && !(p_sys->p_context->height % 16) &&
#if LIBAVCODEC_BUILD >= 4698
        !p_sys->p_context->debug_mv )
#else
        1 )
#endif
    {
        /* Some codecs set pix_fmt only after the 1st frame has been decoded,
         * so we need to do another check in ffmpeg_GetFrameBuf() */
        p_sys->b_direct_rendering = 1;
    }

#ifdef LIBAVCODEC_PP
    p_sys->p_pp = NULL;
    p_sys->b_pp = p_sys->b_pp_async = p_sys->b_pp_init = VLC_FALSE;
    p_sys->p_pp = E_(OpenPostproc)( p_dec, &p_sys->b_pp_async );
#endif

    /* ffmpeg doesn't properly release old pictures when frames are skipped */
    //if( p_sys->b_hurry_up ) p_sys->b_direct_rendering = 0;
    if( p_sys->b_direct_rendering )
    {
        msg_Dbg( p_dec, "using direct rendering" );
        p_sys->p_context->flags |= CODEC_FLAG_EMU_EDGE;
    }

    /* Always use our get_buffer wrapper so we can calculate the
     * PTS correctly */
    p_sys->p_context->get_buffer = ffmpeg_GetFrameBuf;
    p_sys->p_context->release_buffer = ffmpeg_ReleaseFrameBuf;
    p_sys->p_context->opaque = p_dec;

    /* ***** init this codec with special data ***** */
    ffmpeg_InitCodec( p_dec );

    /* ***** misc init ***** */
    p_sys->input_pts = p_sys->input_dts = 0;
    p_sys->i_pts = 0;
    p_sys->b_has_b_frames = VLC_FALSE;
    p_sys->b_first_frame = VLC_TRUE;
    p_sys->i_late_frames = 0;
    p_sys->i_buffer = 0;
    p_sys->i_buffer_orig = 1;
    p_sys->p_buffer_orig = p_sys->p_buffer = malloc( p_sys->i_buffer_orig );

    /* Set output properties */
    p_dec->fmt_out.i_cat = VIDEO_ES;
    p_dec->fmt_out.i_codec = ffmpeg_PixFmtToChroma( p_context->pix_fmt );

    /* Setup palette */
#if LIBAVCODEC_BUILD >= 4688
    if( p_dec->fmt_in.video.p_palette )
        p_sys->p_context->palctrl =
            (AVPaletteControl *)p_dec->fmt_in.video.p_palette;
    else
        p_sys->p_context->palctrl = &palette_control;
#endif

    /* ***** Open the codec ***** */
    vlc_mutex_lock( lockval.p_address );
    if( avcodec_open( p_sys->p_context, p_sys->p_codec ) < 0 )
    {
        vlc_mutex_unlock( lockval.p_address );
        msg_Err( p_dec, "cannot open codec (%s)", p_sys->psz_namecodec );
        free( p_sys );
        return VLC_EGENERIC;
    }
    vlc_mutex_unlock( lockval.p_address );
    msg_Dbg( p_dec, "ffmpeg codec (%s) started", p_sys->psz_namecodec );


    return VLC_SUCCESS;
}

/*****************************************************************************
 * DecodeVideo: Called to decode one or more frames
 *****************************************************************************/
picture_t *E_(DecodeVideo)( decoder_t *p_dec, block_t **pp_block )
{
    decoder_sys_t *p_sys = p_dec->p_sys;
    int b_drawpicture;
    int b_null_size = VLC_FALSE;
    block_t *p_block;

    if( !pp_block || !*pp_block ) return NULL;

    if( !p_sys->p_context->extradata_size && p_dec->fmt_in.i_extra )
        ffmpeg_InitCodec( p_dec );

    p_block = *pp_block;

    if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
    {
        p_sys->i_buffer = 0;
        p_sys->i_pts = 0; /* To make sure we recover properly */

        p_sys->input_pts = p_sys->input_dts = 0;
        p_sys->i_late_frames = 0;

        block_Release( p_block );
        return NULL;
    }

    if( p_block->i_flags & BLOCK_FLAG_PREROLL )
    {
        /* Do not care about late frames when prerolling
         * TODO avoid decoding of non reference frame
         * (ie all B except for H264 where it depends only on nal_ref_idc) */
        p_sys->i_late_frames = 0;
    }

    if( !p_dec->b_pace_control && p_sys->i_late_frames > 0 &&
        mdate() - p_sys->i_late_frames_start > I64C(5000000) )
    {
        if( p_sys->i_pts )
        {
            msg_Err( p_dec, "more than 5 seconds of late video -> "
                     "dropping frame (computer too slow ?)" );
            p_sys->i_pts = 0; /* To make sure we recover properly */
        }
        block_Release( p_block );
        p_sys->i_late_frames--;
        return NULL;
    }

    if( p_block->i_pts > 0 || p_block->i_dts > 0 )
    {
        p_sys->input_pts = p_block->i_pts;
        p_sys->input_dts = p_block->i_dts;

        /* Make sure we don't reuse the same timestamps twice */
        p_block->i_pts = p_block->i_dts = 0;
    }

    /* TODO implement it in a better way */
    /* A good idea could be to decode all I pictures and see for the other */
    if( !p_dec->b_pace_control &&
        p_sys->b_hurry_up && p_sys->i_late_frames > 4 )
    {
        b_drawpicture = 0;
        if( p_sys->i_late_frames < 8 )
        {
            p_sys->p_context->hurry_up = 2;
        }
        else
        {
            /* picture too late, won't decode
             * but break picture until a new I, and for mpeg4 ...*/

            p_sys->i_late_frames--; /* needed else it will never be decrease */
            block_Release( p_block );
            p_sys->i_buffer = 0;
            return NULL;
        }
    }
    else
    {
        if (!(p_block->i_flags & BLOCK_FLAG_PREROLL))
        {
            b_drawpicture = 1;
            p_sys->p_context->hurry_up = 0;
        }
        else
        {
            b_drawpicture = 0;
            p_sys->p_context->hurry_up = 1;
        }
    }