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libavcodec/libopenjpeg.c

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00001 /*
00002  * JPEG 2000 decoding support via OpenJPEG
00003  * Copyright (c) 2009 Jaikrishnan Menon <realityman@gmx.net>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00027 #include "avcodec.h"
00028 #include "libavutil/intreadwrite.h"
00029 #define  OPJ_STATIC
00030 #include <openjpeg.h>
00031 
00032 #define JP2_SIG_TYPE    0x6A502020
00033 #define JP2_SIG_VALUE   0x0D0A870A
00034 
00035 typedef struct {
00036     opj_dparameters_t dec_params;
00037     AVFrame image;
00038 } LibOpenJPEGContext;
00039 
00040 static int check_image_attributes(opj_image_t *image)
00041 {
00042     return(image->comps[0].dx == image->comps[1].dx &&
00043            image->comps[1].dx == image->comps[2].dx &&
00044            image->comps[0].dy == image->comps[1].dy &&
00045            image->comps[1].dy == image->comps[2].dy &&
00046            image->comps[0].prec == image->comps[1].prec &&
00047            image->comps[1].prec == image->comps[2].prec);
00048 }
00049 
00050 static av_cold int libopenjpeg_decode_init(AVCodecContext *avctx)
00051 {
00052     LibOpenJPEGContext *ctx = avctx->priv_data;
00053 
00054     opj_set_default_decoder_parameters(&ctx->dec_params);
00055     avctx->coded_frame = &ctx->image;
00056     return 0;
00057 }
00058 
00059 static int libopenjpeg_decode_frame(AVCodecContext *avctx,
00060                                     void *data, int *data_size,
00061                                     const uint8_t *buf, int buf_size)
00062 {
00063     LibOpenJPEGContext *ctx = avctx->priv_data;
00064     AVFrame *picture = &ctx->image, *output = data;
00065     opj_dinfo_t *dec;
00066     opj_cio_t *stream;
00067     opj_image_t *image;
00068     int width, height, has_alpha = 0, ret = -1;
00069     int x, y, index;
00070     uint8_t *img_ptr;
00071     int adjust[4];
00072 
00073     *data_size = 0;
00074 
00075     // Check if input is a raw jpeg2k codestream or in jp2 wrapping
00076     if((AV_RB32(buf) == 12) &&
00077        (AV_RB32(buf + 4) == JP2_SIG_TYPE) &&
00078        (AV_RB32(buf + 8) == JP2_SIG_VALUE)) {
00079          dec = opj_create_decompress(CODEC_JP2);
00080     } else {
00081          dec = opj_create_decompress(CODEC_J2K);
00082     }
00083 
00084     if(!dec) {
00085         av_log(avctx, AV_LOG_ERROR, "Error initializing decoder.\n");
00086         return -1;
00087     }
00088     opj_set_event_mgr((opj_common_ptr)dec, NULL, NULL);
00089 
00090     // Tie decoder with decoding parameters
00091     opj_setup_decoder(dec, &ctx->dec_params);
00092     stream = opj_cio_open((opj_common_ptr)dec, buf, buf_size);
00093     if(!stream) {
00094         av_log(avctx, AV_LOG_ERROR, "Codestream could not be opened for reading.\n");
00095         opj_destroy_decompress(dec);
00096         return -1;
00097     }
00098 
00099     // Decode the codestream
00100     image = opj_decode_with_info(dec, stream, NULL);
00101     opj_cio_close(stream);
00102     if(!image) {
00103         av_log(avctx, AV_LOG_ERROR, "Error decoding codestream.\n");
00104         opj_destroy_decompress(dec);
00105         return -1;
00106     }
00107     width  = image->comps[0].w;
00108     height = image->comps[0].h;
00109     if(avcodec_check_dimensions(avctx, width, height) < 0) {
00110         av_log(avctx, AV_LOG_ERROR, "%dx%d dimension invalid.\n", width, height);
00111         goto done;
00112     }
00113     avcodec_set_dimensions(avctx, width, height);
00114 
00115     switch(image->numcomps)
00116     {
00117         case 1:  avctx->pix_fmt = PIX_FMT_GRAY8;
00118                  break;
00119         case 3:  if(check_image_attributes(image)) {
00120                      avctx->pix_fmt = PIX_FMT_RGB24;
00121                  } else {
00122                      avctx->pix_fmt = PIX_FMT_GRAY8;
00123                      av_log(avctx, AV_LOG_ERROR, "Only first component will be used.\n");
00124                  }
00125                  break;
00126         case 4:  has_alpha = 1;
00127                  avctx->pix_fmt = PIX_FMT_RGB32;
00128                  break;
00129         default: av_log(avctx, AV_LOG_ERROR, "%d components unsupported.\n", image->numcomps);
00130                  goto done;
00131     }
00132 
00133     if(picture->data[0])
00134         avctx->release_buffer(avctx, picture);
00135 
00136     if(avctx->get_buffer(avctx, picture) < 0) {
00137         av_log(avctx, AV_LOG_ERROR, "Couldn't allocate image buffer.\n");
00138         return -1;
00139     }
00140 
00141     for(x = 0; x < image->numcomps; x++) {
00142         adjust[x] = FFMAX(image->comps[x].prec - 8, 0);
00143     }
00144 
00145     for(y = 0; y < height; y++) {
00146         index = y*width;
00147         img_ptr = picture->data[0] + y*picture->linesize[0];
00148         for(x = 0; x < width; x++, index++) {
00149             *img_ptr++ = image->comps[0].data[index] >> adjust[0];
00150             if(image->numcomps > 2 && check_image_attributes(image)) {
00151                 *img_ptr++ = image->comps[1].data[index] >> adjust[1];
00152                 *img_ptr++ = image->comps[2].data[index] >> adjust[2];
00153                 if(has_alpha)
00154                     *img_ptr++ = image->comps[3].data[index] >> adjust[3];
00155             }
00156         }
00157     }
00158 
00159     *output    = ctx->image;
00160     *data_size = sizeof(AVPicture);
00161     ret = buf_size;
00162 
00163 done:
00164     opj_image_destroy(image);
00165     opj_destroy_decompress(dec);
00166     return ret;
00167 }
00168 
00169 static av_cold int libopenjpeg_decode_close(AVCodecContext *avctx)
00170 {
00171     LibOpenJPEGContext *ctx = avctx->priv_data;
00172 
00173     if(ctx->image.data[0])
00174         avctx->release_buffer(avctx, &ctx->image);
00175     return 0 ;
00176 }
00177 
00178 
00179 AVCodec libopenjpeg_decoder = {
00180     "libopenjpeg",
00181     CODEC_TYPE_VIDEO,
00182     CODEC_ID_JPEG2000,
00183     sizeof(LibOpenJPEGContext),
00184     libopenjpeg_decode_init,
00185     NULL,
00186     libopenjpeg_decode_close,
00187     libopenjpeg_decode_frame,
00188     NULL,
00189     .long_name = NULL_IF_CONFIG_SMALL("OpenJPEG based JPEG 2000 decoder"),
00190 } ;

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