libavcodec/cljr.c

   1 /*
   2  * Cirrus Logic AccuPak (CLJR) codec
   3  * Copyright (c) 2003 Alex Beregszaszi
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * Cirrus Logic AccuPak codec.
  25  */
  26
  27 #include "avcodec.h"
  28 #include "get_bits.h"
  29 #include "put_bits.h"
  30
  31 typedef struct CLJRContext {
  32     AVCodecContext *avctx;
  33     AVFrame         picture;
  34 } CLJRContext;
  35
  36 static av_cold int common_init(AVCodecContext *avctx)
  37 {
  38     CLJRContext * const a = avctx->priv_data;
  39
  40     avctx->coded_frame = &a->picture;
  41     a->avctx = avctx;
  42
  43     return 0;
  44 }
  45
  46 #if CONFIG_CLJR_DECODER
  47 static int decode_frame(AVCodecContext *avctx,
  48                         void *data, int *data_size,
  49                         AVPacket *avpkt)
  50 {
  51     const uint8_t *buf = avpkt->data;
  52     int buf_size       = avpkt->size;
  53     CLJRContext * const a = avctx->priv_data;
  54     GetBitContext gb;
  55     AVFrame *picture = data;
  56     AVFrame * const p = &a->picture;
  57     int x, y;
  58
  59     if (p->data[0])
  60         avctx->release_buffer(avctx, p);
  61
  62     if (buf_size / avctx->height < avctx->width) {
  63         av_log(avctx, AV_LOG_ERROR,
  64                "Resolution larger than buffer size. Invalid header?\n");
  65         return AVERROR_INVALIDDATA;
  66     }
  67
  68     p->reference = 0;
  69     if (avctx->get_buffer(avctx, p) < 0) {
  70         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
  71         return -1;
  72     }
  73     p->pict_type = AV_PICTURE_TYPE_I;
  74     p->key_frame = 1;
  75
  76     init_get_bits(&gb, buf, buf_size * 8);
  77
  78     for (y = 0; y < avctx->height; y++) {
  79         uint8_t *luma = &a->picture.data[0][y * a->picture.linesize[0]];
  80         uint8_t *cb   = &a->picture.data[1][y * a->picture.linesize[1]];
  81         uint8_t *cr   = &a->picture.data[2][y * a->picture.linesize[2]];
  82         for (x = 0; x < avctx->width; x += 4) {
  83             luma[3] = get_bits(&gb, 5) << 3;
  84             luma[2] = get_bits(&gb, 5) << 3;
  85             luma[1] = get_bits(&gb, 5) << 3;
  86             luma[0] = get_bits(&gb, 5) << 3;
  87             luma += 4;
  88             *(cb++) = get_bits(&gb, 6) << 2;
  89             *(cr++) = get_bits(&gb, 6) << 2;
  90         }
  91     }
  92
  93     *picture   = a->picture;
  94     *data_size = sizeof(AVPicture);
  95
  96     return buf_size;
  97 }
  98
  99 static av_cold int decode_init(AVCodecContext *avctx)
 100 {
 101     avctx->pix_fmt = PIX_FMT_YUV411P;
 102     return common_init(avctx);
 103 }
 104
 105 static av_cold int decode_end(AVCodecContext *avctx)
 106 {
 107     CLJRContext *a = avctx->priv_data;
 108
 109     if (a->picture.data[0])
 110         avctx->release_buffer(avctx, &a->picture);
 111     return 0;
 112 }
 113
 114 AVCodec ff_cljr_decoder = {
 115     .name           = "cljr",
 116     .type           = AVMEDIA_TYPE_VIDEO,
 117     .id             = CODEC_ID_CLJR,
 118     .priv_data_size = sizeof(CLJRContext),
 119     .init           = decode_init,
 120     .close          = decode_end,
 121     .decode         = decode_frame,
 122     .capabilities   = CODEC_CAP_DR1,
 123     .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
 124 };
 125 #endif
 126
 127 #if CONFIG_CLJR_ENCODER
 128 static int encode_frame(AVCodecContext *avctx, unsigned char *buf,
 129                         int buf_size, void *data)
 130 {
 131     PutBitContext pb;
 132     AVFrame *p = data;
 133     int x, y;
 134
 135     p->pict_type = AV_PICTURE_TYPE_I;
 136     p->key_frame = 1;
 137
 138     init_put_bits(&pb, buf, buf_size / 8);
 139
 140     for (y = 0; y < avctx->height; y++) {
 141         uint8_t *luma = &p->data[0][y * p->linesize[0]];
 142         uint8_t *cb   = &p->data[1][y * p->linesize[1]];
 143         uint8_t *cr   = &p->data[2][y * p->linesize[2]];
 144         for (x = 0; x < avctx->width; x += 4) {
 145             put_bits(&pb, 5, luma[3] >> 3);
 146             put_bits(&pb, 5, luma[2] >> 3);
 147             put_bits(&pb, 5, luma[1] >> 3);
 148             put_bits(&pb, 5, luma[0] >> 3);
 149             luma += 4;
 150             put_bits(&pb, 6, *(cb++) >> 2);
 151             put_bits(&pb, 6, *(cr++) >> 2);
 152         }
 153     }
 154
 155     flush_put_bits(&pb);
 156
 157     return put_bits_count(&pb) / 8;
 158 }
 159
 160 AVCodec ff_cljr_encoder = {
 161     .name           = "cljr",
 162     .type           = AVMEDIA_TYPE_VIDEO,
 163     .id             = CODEC_ID_CLJR,
 164     .priv_data_size = sizeof(CLJRContext),
 165     .init           = common_init,
 166     .encode         = encode_frame,
 167     .pix_fmts       = (const enum PixelFormat[]) { PIX_FMT_YUV411P,
 168                                                    PIX_FMT_NONE },
 169     .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
 170 };
 171 #endif