ffmpeg.c

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/*
 * FFmpeg main
 * Copyright (c) 2000-2003 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
 */

#include "config.h"
#include <ctype.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <errno.h>
#include <signal.h>
#include <limits.h>
#include "libavformat/avformat.h"
#include "libavdevice/avdevice.h"
#include "libswscale/swscale.h"
#include "libavformat/framehook.h"
#include "libavcodec/opt.h"
#include "libavutil/fifo.h"
#include "libavutil/avstring.h"
#include "libavformat/os_support.h"

#ifdef HAVE_SYS_RESOURCE_H
#include <sys/types.h>
#include <sys/resource.h>
#elif defined(HAVE_GETPROCESSTIMES)
#include <windows.h>
#endif

#if defined(HAVE_TERMIOS_H)
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <termios.h>
#elif defined(HAVE_CONIO_H)
#include <conio.h>
#endif
#undef time //needed because HAVE_AV_CONFIG_H is defined on top
#include <time.h>

#include "cmdutils.h"

#undef NDEBUG
#include <assert.h>

#undef exit

const char program_name[] = "FFmpeg";
const int program_birth_year = 2000;

/* select an input stream for an output stream */
typedef struct AVStreamMap {
    int file_index;
    int stream_index;
    int sync_file_index;
    int sync_stream_index;
} AVStreamMap;

/** select an input file for an output file */
typedef struct AVMetaDataMap {
    int out_file;
    int in_file;
} AVMetaDataMap;

static const OptionDef options[];

#define MAX_FILES 20

static AVFormatContext *input_files[MAX_FILES];
static int64_t input_files_ts_offset[MAX_FILES];
static double input_files_ts_scale[MAX_FILES][MAX_STREAMS];
static int nb_input_files = 0;

static AVFormatContext *output_files[MAX_FILES];
static int nb_output_files = 0;

static AVStreamMap stream_maps[MAX_FILES];
static int nb_stream_maps;

static AVMetaDataMap meta_data_maps[MAX_FILES];
static int nb_meta_data_maps;

static AVInputFormat *file_iformat;
static AVOutputFormat *file_oformat;
static int frame_width  = 0;
static int frame_height = 0;
static float frame_aspect_ratio = 0;
static enum PixelFormat frame_pix_fmt = PIX_FMT_NONE;
static int frame_padtop  = 0;
static int frame_padbottom = 0;
static int frame_padleft  = 0;
static int frame_padright = 0;
static int padcolor[3] = {16,128,128}; /* default to black */
static int frame_topBand  = 0;
static int frame_bottomBand = 0;
static int frame_leftBand  = 0;
static int frame_rightBand = 0;
static int max_frames[4] = {INT_MAX, INT_MAX, INT_MAX, INT_MAX};
static AVRational frame_rate;
static float video_qscale = 0;
static uint16_t *intra_matrix = NULL;
static uint16_t *inter_matrix = NULL;
#if 0 //experimental, (can be removed)
static float video_rc_qsquish=1.0;
static float video_rc_qmod_amp=0;
static int video_rc_qmod_freq=0;
#endif
static const char *video_rc_override_string=NULL;
static int video_disable = 0;
static int video_discard = 0;
static char *video_codec_name = NULL;
static int video_codec_tag = 0;
static int same_quality = 0;
static int do_deinterlace = 0;
static int top_field_first = -1;
static int me_threshold = 0;
static int intra_dc_precision = 8;
static int loop_input = 0;
static int loop_output = AVFMT_NOOUTPUTLOOP;
static int qp_hist = 0;

static int intra_only = 0;
static int audio_sample_rate = 44100;
#define QSCALE_NONE -99999
static float audio_qscale = QSCALE_NONE;
static int audio_disable = 0;
static int audio_channels = 1;
static char  *audio_codec_name = NULL;
static int audio_codec_tag = 0;
static char *audio_language = NULL;

static int subtitle_disable = 0;
static char *subtitle_codec_name = NULL;
static char *subtitle_language = NULL;

static float mux_preload= 0.5;
static float mux_max_delay= 0.7;

static int64_t recording_time = INT64_MAX;
static int64_t start_time = 0;
static int64_t rec_timestamp = 0;
static int64_t input_ts_offset = 0;
static int file_overwrite = 0;
static char *str_title = NULL;
static char *str_author = NULL;
static char *str_copyright = NULL;
static char *str_comment = NULL;
static char *str_genre = NULL;
static char *str_album = NULL;
static int do_benchmark = 0;
static int do_hex_dump = 0;
static int do_pkt_dump = 0;
static int do_psnr = 0;
static int do_pass = 0;
static char *pass_logfilename = NULL;
static int audio_stream_copy = 0;
static int video_stream_copy = 0;
static int subtitle_stream_copy = 0;
static int video_sync_method= -1;
static int audio_sync_method= 0;
static float audio_drift_threshold= 0.1;
static int copy_ts= 0;
static int opt_shortest = 0; //
static int video_global_header = 0;
static char *vstats_filename;
static FILE *vstats_file;
static int opt_programid = 0;

static int rate_emu = 0;

static int  video_channel = 0;
static char *video_standard;

static int audio_volume = 256;

static int using_stdin = 0;
static int using_vhook = 0;
static int verbose = 1;
static int thread_count= 1;
static int q_pressed = 0;
static int64_t video_size = 0;
static int64_t audio_size = 0;
static int64_t extra_size = 0;
static int nb_frames_dup = 0;
static int nb_frames_drop = 0;
static int input_sync;
static uint64_t limit_filesize = 0; //

static int pgmyuv_compatibility_hack=0;
static float dts_delta_threshold = 10;

static unsigned int sws_flags = SWS_BICUBIC;

static const char **opt_names;
static int opt_name_count;
static AVCodecContext *avctx_opts[CODEC_TYPE_NB];
static AVFormatContext *avformat_opts;
static struct SwsContext *sws_opts;
static int64_t timer_start;

static AVBitStreamFilterContext *video_bitstream_filters=NULL;
static AVBitStreamFilterContext *audio_bitstream_filters=NULL;
static AVBitStreamFilterContext *subtitle_bitstream_filters=NULL;
static AVBitStreamFilterContext *bitstream_filters[MAX_FILES][MAX_STREAMS];

#define DEFAULT_PASS_LOGFILENAME "ffmpeg2pass"

struct AVInputStream;

typedef struct AVOutputStream {
    int file_index;          /* file index */
    int index;               /* stream index in the output file */
    int source_index;        /* AVInputStream index */
    AVStream *st;            /* stream in the output file */
    int encoding_needed;     /* true if encoding needed for this stream */
    int frame_number;
    /* input pts and corresponding output pts
       for A/V sync */
    //double sync_ipts;        /* dts from the AVPacket of the demuxer in second units */
    struct AVInputStream *sync_ist; /* input stream to sync against */
    int64_t sync_opts;       /* output frame counter, could be changed to some true timestamp */ //FIXME look at frame_number
    /* video only */
    int video_resample;
    AVFrame pict_tmp;      /* temporary image for resampling */
    struct SwsContext *img_resample_ctx; /* for image resampling */
    int resample_height;

    int video_crop;
    int topBand;             /* cropping area sizes */
    int leftBand;

    int video_pad;
    int padtop;              /* padding area sizes */
    int padbottom;
    int padleft;
    int padright;

    /* audio only */
    int audio_resample;
    ReSampleContext *resample; /* for audio resampling */
    AVFifoBuffer fifo;     /* for compression: one audio fifo per codec */
    FILE *logfile;
} AVOutputStream;

typedef struct AVInputStream {
    int file_index;
    int index;
    AVStream *st;
    int discard;             /* true if stream data should be discarded */
    int decoding_needed;     /* true if the packets must be decoded in 'raw_fifo' */
    int64_t sample_index;      /* current sample */

    int64_t       start;     /* time when read started */
    unsigned long frame;     /* current frame */
    int64_t       next_pts;  /* synthetic pts for cases where pkt.pts
                                is not defined */
    int64_t       pts;       /* current pts */
    int is_start;            /* is 1 at the start and after a discontinuity */
} AVInputStream;

typedef struct AVInputFile {
    int eof_reached;      /* true if eof reached */
    int ist_index;        /* index of first stream in ist_table */
    int buffer_size;      /* current total buffer size */
    int nb_streams;       /* nb streams we are aware of */
} AVInputFile;

#ifdef HAVE_TERMIOS_H

/* init terminal so that we can grab keys */
static struct termios oldtty;
#endif

static void term_exit(void)
{
#ifdef HAVE_TERMIOS_H
    tcsetattr (0, TCSANOW, &oldtty);
#endif
}

static volatile sig_atomic_t received_sigterm = 0;

static void
sigterm_handler(int sig)
{
    received_sigterm = sig;
    term_exit();
}

static void term_init(void)
{
#ifdef HAVE_TERMIOS_H
    struct termios tty;

    tcgetattr (0, &tty);
    oldtty = tty;

    tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
                          |INLCR|IGNCR|ICRNL|IXON);
    tty.c_oflag |= OPOST;
    tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
    tty.c_cflag &= ~(CSIZE|PARENB);
    tty.c_cflag |= CS8;
    tty.c_cc[VMIN] = 1;
    tty.c_cc[VTIME] = 0;

    tcsetattr (0, TCSANOW, &tty);
    signal(SIGQUIT, sigterm_handler); /* Quit (POSIX).  */
#endif

    signal(SIGINT , sigterm_handler); /* Interrupt (ANSI).  */
    signal(SIGTERM, sigterm_handler); /* Termination (ANSI).  */
    /*
    register a function to be called at normal program termination
    */
    atexit(term_exit);
#ifdef CONFIG_BEOS_NETSERVER
    fcntl(0, F_SETFL, fcntl(0, F_GETFL) | O_NONBLOCK);
#endif
}

/* read a key without blocking */
static int read_key(void)
{
#if defined(HAVE_TERMIOS_H)
    int n = 1;
    unsigned char ch;
#ifndef CONFIG_BEOS_NETSERVER
    struct timeval tv;
    fd_set rfds;

    FD_ZERO(&rfds);
    FD_SET(0, &rfds);
    tv.tv_sec = 0;
    tv.tv_usec = 0;
    n = select(1, &rfds, NULL, NULL, &tv);
#endif
    if (n > 0) {
        n = read(0, &ch, 1);
        if (n == 1)
            return ch;

        return n;
    }
#elif defined(HAVE_CONIO_H)
    if(kbhit())
        return(getch());
#endif
    return -1;
}

static int decode_interrupt_cb(void)
{
    return q_pressed || (q_pressed = read_key() == 'q');
}

static int av_exit(int ret)
{
    int i;

    /* close files */
    for(i=0;i<nb_output_files;i++) {
        /* maybe av_close_output_file ??? */
        AVFormatContext *s = output_files[i];
        int j;
        if (!(s->oformat->flags & AVFMT_NOFILE) && s->pb)
            url_fclose(s->pb);
        for(j=0;j<s->nb_streams;j++) {
            av_free(s->streams[j]->codec);
            av_free(s->streams[j]);
        }
        av_free(s);
    }
    for(i=0;i<nb_input_files;i++)
        av_close_input_file(input_files[i]);

    av_free(intra_matrix);
    av_free(inter_matrix);

    if (vstats_file)
        fclose(vstats_file);
    av_free(vstats_filename);

    av_free(opt_names);

    av_free(video_codec_name);
    av_free(audio_codec_name);
    av_free(subtitle_codec_name);

    av_free(video_standard);

#ifdef CONFIG_POWERPC_PERF
    extern void powerpc_display_perf_report(void);
    powerpc_display_perf_report();
#endif /* CONFIG_POWERPC_PERF */

    if (received_sigterm) {
        fprintf(stderr,
            "Received signal %d: terminating.\n",
            (int) received_sigterm);
        exit (255);
    }

    exit(ret); /* not all OS-es handle main() return value */
    return ret;
}

static int read_ffserver_streams(AVFormatContext *s, const char *filename)
{
    int i, err;
    AVFormatContext *ic;
    int nopts = 0;

    err = av_open_input_file(&ic, filename, NULL, FFM_PACKET_SIZE, NULL);
    if (err < 0)
        return err;
    /* copy stream format */
    s->nb_streams = ic->nb_streams;
    for(i=0;i<ic->nb_streams;i++) {
        AVStream *st;

        // FIXME: a more elegant solution is needed
        st = av_mallocz(sizeof(AVStream));
        memcpy(st, ic->streams[i], sizeof(AVStream));
        st->codec = avcodec_alloc_context();
        memcpy(st->codec, ic->streams[i]->codec, sizeof(AVCodecContext));
        s->streams[i] = st;

        if (st->codec->codec_type == CODEC_TYPE_AUDIO && audio_stream_copy)
            st->stream_copy = 1;
        else if (st->codec->codec_type == CODEC_TYPE_VIDEO && video_stream_copy)
            st->stream_copy = 1;

        if(!st->codec->thread_count)
            st->codec->thread_count = 1;
        if(st->codec->thread_count>1)
            avcodec_thread_init(st->codec, st->codec->thread_count);

        if(st->codec->flags & CODEC_FLAG_BITEXACT)
            nopts = 1;
    }

    if (!nopts)
        s->timestamp = av_gettime();

    av_close_input_file(ic);
    return 0;
}

static double
get_sync_ipts(const AVOutputStream *ost)
{
    const AVInputStream *ist = ost->sync_ist;
    return (double)(ist->pts - start_time)/AV_TIME_BASE;
}

static void write_frame(AVFormatContext *s, AVPacket *pkt, AVCodecContext *avctx, AVBitStreamFilterContext *bsfc){
    int ret;

    while(bsfc){
        AVPacket new_pkt= *pkt;
        int a= av_bitstream_filter_filter(bsfc, avctx, NULL,
                                          &new_pkt.data, &new_pkt.size,
                                          pkt->data, pkt->size,
                                          pkt->flags & PKT_FLAG_KEY);
        if(a>0){
            av_free_packet(pkt);
            new_pkt.destruct= av_destruct_packet;
        } else if(a<0){
            fprintf(stderr, "%s failed for stream %d, codec %s",
                    bsfc->filter->name, pkt->stream_index,
                    avctx->codec ? avctx->codec->name : "copy");
            print_error("", a);
        }
        *pkt= new_pkt;

        bsfc= bsfc->next;
    }

    ret= av_interleaved_write_frame(s, pkt);
    if(ret < 0){
        print_error("av_interleaved_write_frame()", ret);
        av_exit(1);
    }
}

#define MAX_AUDIO_PACKET_SIZE (128 * 1024)

static void do_audio_out(AVFormatContext *s,
                         AVOutputStream *ost,
                         AVInputStream *ist,
                         unsigned char *buf, int size)
{
    uint8_t *buftmp;
    static uint8_t *audio_buf = NULL;
    static uint8_t *audio_out = NULL;
    const int audio_out_size= 4*MAX_AUDIO_PACKET_SIZE;

    int size_out, frame_bytes, ret;
    AVCodecContext *enc= ost->st->codec;
    AVCodecContext *dec= ist->st->codec;

    /* SC: dynamic allocation of buffers */
    if (!audio_buf)
        audio_buf = av_malloc(2*MAX_AUDIO_PACKET_SIZE);
    if (!audio_out)
        audio_out = av_malloc(audio_out_size);
    if (!audio_buf || !audio_out)
        return;               /* Should signal an error ! */

    if (enc->channels != dec->channels)
        ost->audio_resample = 1;

    if (ost->audio_resample && !ost->resample) {
        ost->resample = audio_resample_init(enc->channels,    dec->channels,
                                            enc->sample_rate, dec->sample_rate);
        if (!ost->resample) {
            fprintf(stderr, "Can not resample %d channels @ %d Hz to %d channels @ %d Hz\n",
                    dec->channels, dec->sample_rate,
                    enc->channels, enc->sample_rate);
            av_exit(1);
        }
    }

    if(audio_sync_method){
        double delta = get_sync_ipts(ost) * enc->sample_rate - ost->sync_opts
                - av_fifo_size(&ost->fifo)/(ost->st->codec->channels * 2);
        double idelta= delta*ist->st->codec->sample_rate / enc->sample_rate;
        int byte_delta= ((int)idelta)*2*ist->st->codec->channels;

        //FIXME resample delay
        if(fabs(delta) > 50){
            if(ist->is_start || fabs(delta) > audio_drift_threshold*enc->sample_rate){
                if(byte_delta < 0){
                    byte_delta= FFMAX(byte_delta, -size);
                    size += byte_delta;
                    buf  -= byte_delta;
                    if(verbose > 2)
                        fprintf(stderr, "discarding %d audio samples\n", (int)-delta);
                    if(!size)
                        return;
                    ist->is_start=0;
                }else{
                    static uint8_t *input_tmp= NULL;
                    input_tmp= av_realloc(input_tmp, byte_delta + size);

                    if(byte_delta + size <= MAX_AUDIO_PACKET_SIZE)
                        ist->is_start=0;
                    else
                        byte_delta= MAX_AUDIO_PACKET_SIZE - size;

                    memset(input_tmp, 0, byte_delta);
                    memcpy(input_tmp + byte_delta, buf, size);
                    buf= input_tmp;
                    size += byte_delta;
                    if(verbose > 2)
                        fprintf(stderr, "adding %d audio samples of silence\n", (int)delta);
                }
            }else if(audio_sync_method>1){
                int comp= av_clip(delta, -audio_sync_method, audio_sync_method);
                assert(ost->audio_resample);
                if(verbose > 2)
                    fprintf(stderr, "compensating audio timestamp drift:%f compensation:%d in:%d\n", delta, comp, enc->sample_rate);
//                fprintf(stderr, "drift:%f len:%d opts:%"PRId64" ipts:%"PRId64" fifo:%d\n", delta, -1, ost->sync_opts, (int64_t)(get_sync_ipts(ost) * enc->sample_rate), av_fifo_size(&ost->fifo)/(ost->st->codec->channels * 2));
                av_resample_compensate(*(struct AVResampleContext**)ost->resample, comp, enc->sample_rate);
            }
        }
    }else
        ost->sync_opts= lrintf(get_sync_ipts(ost) * enc->sample_rate)
                        - av_fifo_size(&ost->fifo)/(ost->st->codec->channels * 2); //FIXME wrong

    if (ost->audio_resample) {
        buftmp = audio_buf;
        size_out = audio_resample(ost->resample,
                                  (short *)buftmp, (short *)buf,
                                  size / (ist->st->codec->channels * 2));
        size_out = size_out * enc->channels * 2;
    } else {
        buftmp = buf;
        size_out = size;
    }

    /* now encode as many frames as possible */
    if (enc->frame_size > 1) {
        /* output resampled raw samples */
        av_fifo_realloc(&ost->fifo, av_fifo_size(&ost->fifo) + size_out);
        av_fifo_generic_write(&ost->fifo, buftmp, size_out, NULL);

        frame_bytes = enc->frame_size * 2 * enc->channels;

        while (av_fifo_size(&ost->fifo) >= frame_bytes) {
            AVPacket pkt;
            av_init_packet(&pkt);

            av_fifo_read(&ost->fifo, audio_buf, frame_bytes);

            //FIXME pass ost->sync_opts as AVFrame.pts in avcodec_encode_audio()

            ret = avcodec_encode_audio(enc, audio_out, audio_out_size,
                                       (short *)audio_buf);
            audio_size += ret;
            pkt.stream_index= ost->index;
            pkt.data= audio_out;
            pkt.size= ret;
            if(enc->coded_frame && enc->coded_frame->pts != AV_NOPTS_VALUE)
                pkt.pts= av_rescale_q(enc->coded_frame->pts, enc->time_base, ost->st->time_base);
            pkt.flags |= PKT_FLAG_KEY;
            write_frame(s, &pkt, ost->st->codec, bitstream_filters[ost->file_index][pkt.stream_index]);

            ost->sync_opts += enc->frame_size;
        }
    } else {
        AVPacket pkt;
        av_init_packet(&pkt);

        ost->sync_opts += size_out / (2 * enc->channels);

        /* output a pcm frame */
        /* XXX: change encoding codec API to avoid this ? */
        switch(enc->codec->id) {
        case CODEC_ID_PCM_S32LE:
        case CODEC_ID_PCM_S32BE:
        case CODEC_ID_PCM_U32LE:
        case CODEC_ID_PCM_U32BE:
            size_out = size_out << 1;
            break;
        case CODEC_ID_PCM_S24LE:
        case CODEC_ID_PCM_S24BE:
        case CODEC_ID_PCM_U24LE:
        case CODEC_ID_PCM_U24BE:
        case CODEC_ID_PCM_S24DAUD:
            size_out = size_out / 2 * 3;
            break;
        case CODEC_ID_PCM_S16LE:
        case CODEC_ID_PCM_S16BE:
        case CODEC_ID_PCM_U16LE:
        case CODEC_ID_PCM_U16BE:
            break;
        default:
            size_out = size_out >> 1;
            break;
        }
        //FIXME pass ost->sync_opts as AVFrame.pts in avcodec_encode_audio()
        ret = avcodec_encode_audio(enc, audio_out, size_out,
                                   (short *)buftmp);
        audio_size += ret;
        pkt.stream_index= ost->index;
        pkt.data= audio_out;
        pkt.size= ret;
        if(enc->coded_frame && enc->coded_frame->pts != AV_NOPTS_VALUE)
            pkt.pts= av_rescale_q(enc->coded_frame->pts, enc->time_base, ost->st->time_base);
        pkt.flags |= PKT_FLAG_KEY;
        write_frame(s, &pkt, ost->st->codec, bitstream_filters[ost->file_index][pkt.stream_index]);
    }
}

static void pre_process_video_frame(AVInputStream *ist, AVPicture *picture, void **bufp)
{
    AVCodecContext *dec;
    AVPicture *picture2;
    AVPicture picture_tmp;
    uint8_t *buf = 0;

    dec = ist->st->codec;

    /* deinterlace : must be done before any resize */
    if (do_deinterlace || using_vhook) {
        int size;

        /* create temporary picture */
        size = avpicture_get_size(dec->pix_fmt, dec->width, dec->height);
        buf = av_malloc(size);
        if (!buf)
            return;

        picture2 = &picture_tmp;
        avpicture_fill(picture2, buf, dec->pix_fmt, dec->width, dec->height);

        if (do_deinterlace){
            if(avpicture_deinterlace(picture2, picture,
                                     dec->pix_fmt, dec->width, dec->height) < 0) {
                /* if error, do not deinterlace */
                av_free(buf);
                buf = NULL;
                picture2 = picture;
            }
        } else {
            av_picture_copy(picture2, picture, dec->pix_fmt, dec->width, dec->height);
        }
    } else {
        picture2 = picture;
    }

    if (ENABLE_VHOOK)
        frame_hook_process(picture2, dec->pix_fmt, dec->width, dec->height,
                           1000000 * ist->pts / AV_TIME_BASE);

    if (picture != picture2)
        *picture = *picture2;
    *bufp = buf;
}

/* we begin to correct av delay at this threshold */
#define AV_DELAY_MAX 0.100

static void do_subtitle_out(AVFormatContext *s,
                            AVOutputStream *ost,
                            AVInputStream *ist,
                            AVSubtitle *sub,
                            int64_t pts)
{
    static uint8_t *subtitle_out = NULL;
    int subtitle_out_max_size = 65536;
    int subtitle_out_size, nb, i;
    AVCodecContext *enc;
    AVPacket pkt;

    if (pts == AV_NOPTS_VALUE) {
        fprintf(stderr, "Subtitle packets must have a pts\n");
        return;
    }

    enc = ost->st->codec;

    if (!subtitle_out) {
        subtitle_out = av_malloc(subtitle_out_max_size);
    }

    /* Note: DVB subtitle need one packet to draw them and one other
       packet to clear them */
    /* XXX: signal it in the codec context ? */
    if (enc->codec_id == CODEC_ID_DVB_SUBTITLE)
        nb = 2;
    else
        nb = 1;

    for(i = 0; i < nb; i++) {
        subtitle_out_size = avcodec_encode_subtitle(enc, subtitle_out,
                                                    subtitle_out_max_size, sub);

        av_init_packet(&pkt);
        pkt.stream_index = ost->index;
        pkt.data = subtitle_out;
        pkt.size = subtitle_out_size;
        pkt.pts = av_rescale_q(pts, ist->st->time_base, ost->st->time_base);
        if (enc->codec_id == CODEC_ID_DVB_SUBTITLE) {
            /* XXX: the pts correction is handled here. Maybe handling
               it in the codec would be better */
            if (i == 0)
                pkt.pts += 90 * sub->start_display_time;
            else
                pkt.pts += 90 * sub->end_display_time;
        }
        write_frame(s, &pkt, ost->st->codec, bitstream_filters[ost->file_index][pkt.stream_index]);
    }
}

static int bit_buffer_size= 1024*256;
static uint8_t *bit_buffer= NULL;

static void do_video_out(AVFormatContext *s,
                         AVOutputStream *ost,
                         AVInputStream *ist,
                         AVFrame *in_picture,
                         int *frame_size)
{
    int nb_frames, i, ret;
    AVFrame *final_picture, *formatted_picture, *resampling_dst, *padding_src;
    AVFrame picture_crop_temp, picture_pad_temp;
    AVCodecContext *enc, *dec;

    avcodec_get_frame_defaults(&picture_crop_temp);
    avcodec_get_frame_defaults(&picture_pad_temp);

    enc = ost->st->codec;
    dec = ist->st->codec;