ffmpeg.c

F:图像处理资料264264书籍ffmpeg-0.4.9-pre1VideoStream.rar 一个视频解压缩源代码

            /* create temporary picture */
            size = avpicture_get_size(enc->pix_fmt, enc->width, enc->height);
            buf = av_malloc(size);
            if (!buf)
                return;
            final_picture = &picture_format_temp;
            avpicture_fill((AVPicture*)final_picture, buf, enc->pix_fmt, enc->width, enc->height);
        
            if (img_convert((AVPicture*)final_picture, enc->pix_fmt, 
                            (AVPicture*)&ost->pict_tmp, PIX_FMT_YUV420P, 
                            enc->width, enc->height) < 0) {

                if (verbose >= 0)
                    fprintf(stderr, "pixel format conversion not handled\n");

                goto the_end;
            }
	}
    } else if (ost->video_crop) {
        picture_crop_temp.data[0] = formatted_picture->data[0] +
                (ost->topBand * formatted_picture->linesize[0]) + ost->leftBand;

        picture_crop_temp.data[1] = formatted_picture->data[1] +
                ((ost->topBand >> 1) * formatted_picture->linesize[1]) +
                (ost->leftBand >> 1);

        picture_crop_temp.data[2] = formatted_picture->data[2] +
                ((ost->topBand >> 1) * formatted_picture->linesize[2]) +
                (ost->leftBand >> 1);

        picture_crop_temp.linesize[0] = formatted_picture->linesize[0];
        picture_crop_temp.linesize[1] = formatted_picture->linesize[1];
        picture_crop_temp.linesize[2] = formatted_picture->linesize[2];
        final_picture = &picture_crop_temp;
    } else if (ost->video_pad) {
        final_picture = &ost->pict_tmp;

        for (i = 0; i < 3; i++) {
            uint8_t *optr, *iptr;
            int shift = (i == 0) ? 0 : 1;
            int y, yheight;
            
            /* set offset to start writing image into */
            optr = final_picture->data[i] + (((final_picture->linesize[i] * 
                            ost->padtop) + ost->padleft) >> shift);
            iptr = formatted_picture->data[i];

            yheight = (enc->height - ost->padtop - ost->padbottom) >> shift;
            for (y = 0; y < yheight; y++) {
                /* copy unpadded image row into padded image row */
                memcpy(optr, iptr, formatted_picture->linesize[i]);
                optr += final_picture->linesize[i];
                iptr += formatted_picture->linesize[i];
            }
        }

        fill_pad_region((AVPicture*)final_picture, enc->height, enc->width,
                ost->padtop, ost->padbottom, ost->padleft, ost->padright,
                padcolor);
        
        if (enc->pix_fmt != PIX_FMT_YUV420P) {
            int size;

            av_free(buf);
            /* create temporary picture */
            size = avpicture_get_size(enc->pix_fmt, enc->width, enc->height);
            buf = av_malloc(size);
            if (!buf)
                return;
            final_picture = &picture_format_temp;
            avpicture_fill((AVPicture*)final_picture, buf, enc->pix_fmt, enc->width, enc->height);

            if (img_convert((AVPicture*)final_picture, enc->pix_fmt, 
                        (AVPicture*)&ost->pict_tmp, PIX_FMT_YUV420P, 
                        enc->width, enc->height) < 0) {

                if (verbose >= 0)
                    fprintf(stderr, "pixel format conversion not handled\n");

                goto the_end;
            }
        }
    } else {
        final_picture = formatted_picture;
    }
    /* duplicates frame if needed */
    /* XXX: pb because no interleaving */
    for(i=0;i<nb_frames;i++) {
        AVPacket pkt;
        av_init_packet(&pkt);
        pkt.stream_index= ost->index;

        if (s->oformat->flags & AVFMT_RAWPICTURE) {
            /* raw pictures are written as AVPicture structure to
               avoid any copies. We support temorarily the older
               method. */
            AVFrame* old_frame = enc->coded_frame;
	    enc->coded_frame = dec->coded_frame; //FIXME/XXX remove this hack
            pkt.data= (uint8_t *)final_picture;
            pkt.size=  sizeof(AVPicture);
            if(dec->coded_frame)
                pkt.pts= dec->coded_frame->pts;
            if(dec->coded_frame && dec->coded_frame->key_frame)
                pkt.flags |= PKT_FLAG_KEY;

            av_interleaved_write_frame(s, &pkt);
	    enc->coded_frame = old_frame;
        } else {
            AVFrame big_picture;

            big_picture= *final_picture;
            /* better than nothing: use input picture interlaced
               settings */
            big_picture.interlaced_frame = in_picture->interlaced_frame;
            if(do_interlace_me || do_interlace_dct){
                if(top_field_first == -1)
                    big_picture.top_field_first = in_picture->top_field_first;
                else
                    big_picture.top_field_first = top_field_first;
            }

            /* handles sameq here. This is not correct because it may
               not be a global option */
            if (same_quality) {
                big_picture.quality = ist->st->quality;
            }else
                big_picture.quality = ost->st->quality;
            if(!me_threshold)
                big_picture.pict_type = 0;
//            big_picture.pts = AV_NOPTS_VALUE;
            big_picture.pts= av_rescale(ost->sync_opts, AV_TIME_BASE*(int64_t)enc->frame_rate_base, enc->frame_rate);
//av_log(NULL, AV_LOG_DEBUG, "%lld -> encoder\n", ost->sync_opts);
            ret = avcodec_encode_video(enc, 
                                       bit_buffer, VIDEO_BUFFER_SIZE,
                                       &big_picture);
            //enc->frame_number = enc->real_pict_num;
            if(ret){
                pkt.data= bit_buffer;
                pkt.size= ret;
                if(enc->coded_frame)
                    pkt.pts= enc->coded_frame->pts;
/*av_log(NULL, AV_LOG_DEBUG, "encoder -> %lld/%lld\n", 
   pkt.pts != AV_NOPTS_VALUE ? av_rescale(pkt.pts, enc->frame_rate, AV_TIME_BASE*(int64_t)enc->frame_rate_base) : -1,
   pkt.dts != AV_NOPTS_VALUE ? av_rescale(pkt.dts, enc->frame_rate, AV_TIME_BASE*(int64_t)enc->frame_rate_base) : -1);*/

                if(enc->coded_frame && enc->coded_frame->key_frame)
                    pkt.flags |= PKT_FLAG_KEY;
                av_interleaved_write_frame(s, &pkt);
                *frame_size = ret;
                //fprintf(stderr,"\nFrame: %3d %3d size: %5d type: %d",
                //        enc->frame_number-1, enc->real_pict_num, ret,
                //        enc->pict_type);
                /* if two pass, output log */
                if (ost->logfile && enc->stats_out) {
                    fprintf(ost->logfile, "%s", enc->stats_out);
                }
            }
        }
        ost->sync_opts++;
        ost->frame_number++;
    }
 the_end:
    av_free(buf);
    av_free(buf1);
}

static double psnr(double d){
    if(d==0) return INFINITY;
    return -10.0*log(d)/log(10.0);
}

static void do_video_stats(AVFormatContext *os, AVOutputStream *ost, 
                           int frame_size)
{
    static FILE *fvstats=NULL;
    char filename[40];
    time_t today2;
    struct tm *today;
    AVCodecContext *enc;
    int frame_number;
    int64_t ti;
    double ti1, bitrate, avg_bitrate;
    
    if (!fvstats) {
        today2 = time(NULL);
        today = localtime(&today2);
        sprintf(filename, "vstats_%02d%02d%02d.log", today->tm_hour,
                                               today->tm_min,
                                               today->tm_sec);
        fvstats = fopen(filename,"w");
        if (!fvstats) {
            perror("fopen");
            exit(1);
        }
    }
    
    ti = MAXINT64;
    enc = &ost->st->codec;
    if (enc->codec_type == CODEC_TYPE_VIDEO) {
        frame_number = ost->frame_number;
        fprintf(fvstats, "frame= %5d q= %2.1f ", frame_number, enc->coded_frame->quality/(float)FF_QP2LAMBDA);
        if (enc->flags&CODEC_FLAG_PSNR)
            fprintf(fvstats, "PSNR= %6.2f ", psnr(enc->coded_frame->error[0]/(enc->width*enc->height*255.0*255.0)));
        
        fprintf(fvstats,"f_size= %6d ", frame_size);
        /* compute pts value */
        ti1 = (double)ost->sync_opts *enc->frame_rate_base / enc->frame_rate;
        if (ti1 < 0.01)
            ti1 = 0.01;
    
        bitrate = (double)(frame_size * 8) * enc->frame_rate / enc->frame_rate_base / 1000.0;
        avg_bitrate = (double)(video_size * 8) / ti1 / 1000.0;
        fprintf(fvstats, "s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s ",
            (double)video_size / 1024, ti1, bitrate, avg_bitrate);
        fprintf(fvstats,"type= %c\n", av_get_pict_type_char(enc->coded_frame->pict_type));        
    }
}

static void print_report(AVFormatContext **output_files,
			 AVOutputStream **ost_table, int nb_ostreams,
			 int is_last_report)
{
    char buf[1024];
    AVOutputStream *ost;
    AVFormatContext *oc, *os;
    int64_t total_size;
    AVCodecContext *enc;
    int frame_number, vid, i;
    double bitrate, ti1, pts;
    static int64_t last_time = -1;
    
    if (!is_last_report) {
        int64_t cur_time;
        /* display the report every 0.5 seconds */
        cur_time = av_gettime();
        if (last_time == -1) {
            last_time = cur_time;
            return;
        } 
        if ((cur_time - last_time) < 500000)
            return;
        last_time = cur_time;
    }


    oc = output_files[0];

    total_size = url_ftell(&oc->pb);
    
    buf[0] = '\0';
    ti1 = 1e10;
    vid = 0;
    for(i=0;i<nb_ostreams;i++) {
        ost = ost_table[i];
        os = output_files[ost->file_index];
        enc = &ost->st->codec;
        if (vid && enc->codec_type == CODEC_TYPE_VIDEO) {
            sprintf(buf + strlen(buf), "q=%2.1f ",
                    enc->coded_frame->quality/(float)FF_QP2LAMBDA);
        }
        if (!vid && enc->codec_type == CODEC_TYPE_VIDEO) {
            frame_number = ost->frame_number;
            sprintf(buf + strlen(buf), "frame=%5d q=%2.1f ",
                    frame_number, enc->coded_frame ? enc->coded_frame->quality/(float)FF_QP2LAMBDA : 0);
            if(is_last_report)
                sprintf(buf + strlen(buf), "L");
            if (enc->flags&CODEC_FLAG_PSNR){
                int j;
                double error, error_sum=0;
                double scale, scale_sum=0;
                char type[3]= {'Y','U','V'};
                sprintf(buf + strlen(buf), "PSNR=");
                for(j=0; j<3; j++){
                    if(is_last_report){
                        error= enc->error[j];
                        scale= enc->width*enc->height*255.0*255.0*frame_number;
                    }else{
                        error= enc->coded_frame->error[j];
                        scale= enc->width*enc->height*255.0*255.0;
                    }
                    if(j) scale/=4;
                    error_sum += error;
                    scale_sum += scale;
                    sprintf(buf + strlen(buf), "%c:%2.2f ", type[j], psnr(error/scale));
                }
                sprintf(buf + strlen(buf), "*:%2.2f ", psnr(error_sum/scale_sum));
            }
            vid = 1;
        }
        /* compute min output value */
        pts = (double)ost->st->pts.val * ost->st->time_base.num / ost->st->time_base.den;
        if ((pts < ti1) && (pts > 0))
            ti1 = pts;
    }
    if (ti1 < 0.01)
        ti1 = 0.01;
    
    if (verbose || is_last_report) {
        bitrate = (double)(total_size * 8) / ti1 / 1000.0;
        
        sprintf(buf + strlen(buf), 
            "size=%8.0fkB time=%0.1f bitrate=%6.1fkbits/s",
            (double)total_size / 1024, ti1, bitrate);

	if (verbose > 1)
	  sprintf(buf + strlen(buf), " dup=%d drop=%d",
		  nb_frames_dup, nb_frames_drop);
        
        if (verbose >= 0)
            fprintf(stderr, "%s    \r", buf);

        fflush(stderr);
    }
        
    if (is_last_report && verbose >= 0){
        int64_t raw= audio_size + video_size + extra_size;
        fprintf(stderr, "\n");
        fprintf(stderr, "video:%1.0fkB audio:%1.0fkB global headers:%1.0fkB muxing overhead %f%%\n",
                video_size/1024.0,
                audio_size/1024.0,
                extra_size/1024.0,
                100.0*(total_size - raw)/raw
        );
    }
}

/* pkt = NULL means EOF (needed to flush decoder buffers) */
static int output_packet(AVInputStream *ist, int ist_index,
                         AVOutputStream **ost_table, int nb_ostreams,
                         const AVPacket *pkt)
{
    AVFormatContext *os;
    AVOutputStream *ost;
    uint8_t *ptr;
    int len, ret, i;
    uint8_t *data_buf;
    int data_size, got_picture;
    AVFrame picture;
    short samples[AVCODEC_MAX_AUDIO_FRAME_SIZE / 2];
    void *buffer_to_free;

    if (pkt && pkt->dts != AV_NOPTS_VALUE) { //FIXME seems redundant, as libavformat does this too
        ist->next_pts = ist->pts = pkt->dts;
    } else {
        assert(ist->pts == ist->next_pts);
    }

    if (pkt == NULL) {
        /* EOF handling */
        ptr = NULL;
        len = 0;
        goto handle_eof;
    }

    len = pkt->size;
    ptr = pkt->data;
    while (len > 0) {
    handle_eof:
        /* decode the packet if needed */
        data_buf = NULL; /* fail safe */
        data_size = 0;
        if (ist->decoding_needed) {
            switch(ist->st->codec.codec_type) {
            case CODEC_TYPE_AUDIO:
                    /* XXX: could avoid copy if PCM 16 bits with same
                       endianness as CPU */