Libav 0.7.1
libavcodec/cljr.c
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00001 /*
00002  * Cirrus Logic AccuPak (CLJR) codec
00003  * Copyright (c) 2003 Alex Beregszaszi
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav 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  * Libav 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 Libav; 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 "dsputil.h"
00029 #include "get_bits.h"
00030 
00031 /* Disable the encoder. */
00032 #undef CONFIG_CLJR_ENCODER
00033 #define CONFIG_CLJR_ENCODER 0
00034 
00035 typedef struct CLJRContext{
00036     AVCodecContext *avctx;
00037     AVFrame picture;
00038     int delta[16];
00039     int offset[4];
00040     GetBitContext gb;
00041 } CLJRContext;
00042 
00043 static int decode_frame(AVCodecContext *avctx,
00044                         void *data, int *data_size,
00045                         AVPacket *avpkt)
00046 {
00047     const uint8_t *buf = avpkt->data;
00048     int buf_size = avpkt->size;
00049     CLJRContext * const a = avctx->priv_data;
00050     AVFrame *picture = data;
00051     AVFrame * const p= (AVFrame*)&a->picture;
00052     int x, y;
00053 
00054     if(p->data[0])
00055         avctx->release_buffer(avctx, p);
00056 
00057     if(buf_size/avctx->height < avctx->width) {
00058         av_log(avctx, AV_LOG_ERROR, "Resolution larger than buffer size. Invalid header?\n");
00059         return -1;
00060     }
00061 
00062     p->reference= 0;
00063     if(avctx->get_buffer(avctx, p) < 0){
00064         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00065         return -1;
00066     }
00067     p->pict_type= AV_PICTURE_TYPE_I;
00068     p->key_frame= 1;
00069 
00070     init_get_bits(&a->gb, buf, buf_size * 8);
00071 
00072     for(y=0; y<avctx->height; y++){
00073         uint8_t *luma= &a->picture.data[0][ y*a->picture.linesize[0] ];
00074         uint8_t *cb= &a->picture.data[1][ y*a->picture.linesize[1] ];
00075         uint8_t *cr= &a->picture.data[2][ y*a->picture.linesize[2] ];
00076         for(x=0; x<avctx->width; x+=4){
00077                 luma[3] = get_bits(&a->gb, 5) << 3;
00078             luma[2] = get_bits(&a->gb, 5) << 3;
00079             luma[1] = get_bits(&a->gb, 5) << 3;
00080             luma[0] = get_bits(&a->gb, 5) << 3;
00081             luma+= 4;
00082             *(cb++) = get_bits(&a->gb, 6) << 2;
00083             *(cr++) = get_bits(&a->gb, 6) << 2;
00084         }
00085     }
00086 
00087     *picture= *(AVFrame*)&a->picture;
00088     *data_size = sizeof(AVPicture);
00089 
00090     emms_c();
00091 
00092     return buf_size;
00093 }
00094 
00095 #if CONFIG_CLJR_ENCODER
00096 static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
00097     CLJRContext * const a = avctx->priv_data;
00098     AVFrame *pict = data;
00099     AVFrame * const p= (AVFrame*)&a->picture;
00100     int size;
00101 
00102     *p = *pict;
00103     p->pict_type= AV_PICTURE_TYPE_I;
00104     p->key_frame= 1;
00105 
00106     emms_c();
00107 
00108     align_put_bits(&a->pb);
00109     while(get_bit_count(&a->pb)&31)
00110         put_bits(&a->pb, 8, 0);
00111 
00112     size= get_bit_count(&a->pb)/32;
00113 
00114     return size*4;
00115 }
00116 #endif
00117 
00118 static av_cold void common_init(AVCodecContext *avctx){
00119     CLJRContext * const a = avctx->priv_data;
00120 
00121     avctx->coded_frame= (AVFrame*)&a->picture;
00122     a->avctx= avctx;
00123 }
00124 
00125 static av_cold int decode_init(AVCodecContext *avctx){
00126 
00127     common_init(avctx);
00128 
00129     avctx->pix_fmt= PIX_FMT_YUV411P;
00130 
00131     return 0;
00132 }
00133 
00134 #if CONFIG_CLJR_ENCODER
00135 static av_cold int encode_init(AVCodecContext *avctx){
00136 
00137     common_init(avctx);
00138 
00139     return 0;
00140 }
00141 #endif
00142 
00143 AVCodec ff_cljr_decoder = {
00144     "cljr",
00145     AVMEDIA_TYPE_VIDEO,
00146     CODEC_ID_CLJR,
00147     sizeof(CLJRContext),
00148     decode_init,
00149     NULL,
00150     NULL,
00151     decode_frame,
00152     CODEC_CAP_DR1,
00153     .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
00154 };
00155 
00156 #if CONFIG_CLJR_ENCODER
00157 AVCodec ff_cljr_encoder = {
00158     "cljr",
00159     AVMEDIA_TYPE_VIDEO,
00160     CODEC_ID_CLJR,
00161     sizeof(CLJRContext),
00162     encode_init,
00163     encode_frame,
00164     //encode_end,
00165     .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
00166 };
00167 #endif