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     AVFrame         picture;
  33 } CLJRContext;
  34
  35 static av_cold int common_init(AVCodecContext *avctx)
  36 {
  37     CLJRContext * const a = avctx->priv_data;
  38
  39     avctx->coded_frame = &a->picture;
  40
  41     return 0;
  42 }
  43
  44 #if CONFIG_CLJR_DECODER
  45 static int decode_frame(AVCodecContext *avctx,
  46                         void *data, int *data_size,
  47                         AVPacket *avpkt)
  48 {
  49     const uint8_t *buf = avpkt->data;
  50     int buf_size       = avpkt->size;
  51     CLJRContext * const a = avctx->priv_data;
  52     GetBitContext gb;
  53     AVFrame *picture = data;
  54     AVFrame * const p = &a->picture;
  55     int x, y;
  56
  57     if (p->data[0])
  58         avctx->release_buffer(avctx, p);
  59
  60     if (buf_size / avctx->height < avctx->width) {
  61         av_log(avctx, AV_LOG_ERROR,
  62                "Resolution larger than buffer size. Invalid header?\n");
  63         return AVERROR_INVALIDDATA;
  64     }
  65
  66     p->reference = 0;
  67     if (avctx->get_buffer(avctx, p) < 0) {
  68         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
  69         return -1;
  70     }
  71     p->pict_type = AV_PICTURE_TYPE_I;
  72     p->key_frame = 1;
  73
  74     init_get_bits(&gb, buf, buf_size * 8);
  75
  76     for (y = 0; y < avctx->height; y++) {
  77         uint8_t *luma = &a->picture.data[0][y * a->picture.linesize[0]];
  78         uint8_t *cb   = &a->picture.data[1][y * a->picture.linesize[1]];
  79         uint8_t *cr   = &a->picture.data[2][y * a->picture.linesize[2]];
  80         for (x = 0; x < avctx->width; x += 4) {
  81             luma[3] = get_bits(&gb, 5) << 3;
  82             luma[2] = get_bits(&gb, 5) << 3;
  83             luma[1] = get_bits(&gb, 5) << 3;
  84             luma[0] = get_bits(&gb, 5) << 3;
  85             luma += 4;
  86             *(cb++) = get_bits(&gb, 6) << 2;
  87             *(cr++) = get_bits(&gb, 6) << 2;
  88         }
  89     }
  90
  91     *picture   = a->picture;
  92     *data_size = sizeof(AVPicture);
  93
  94     return buf_size;
  95 }
  96
  97 static av_cold int decode_init(AVCodecContext *avctx)
  98 {
  99     avctx->pix_fmt = PIX_FMT_YUV411P;
 100     return common_init(avctx);
 101 }
 102
 103 static av_cold int decode_end(AVCodecContext *avctx)
 104 {
 105     CLJRContext *a = avctx->priv_data;
 106
 107     if (a->picture.data[0])
 108         avctx->release_buffer(avctx, &a->picture);
 109     return 0;
 110 }
 111
 112 AVCodec ff_cljr_decoder = {
 113     .name           = "cljr",
 114     .type           = AVMEDIA_TYPE_VIDEO,
 115     .id             = CODEC_ID_CLJR,
 116     .priv_data_size = sizeof(CLJRContext),
 117     .init           = decode_init,
 118     .close          = decode_end,
 119     .decode         = decode_frame,
 120     .capabilities   = CODEC_CAP_DR1,
 121     .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
 122 };
 123 #endif
 124
 125 #if CONFIG_CLJR_ENCODER
 126 static int encode_frame(AVCodecContext *avctx, unsigned char *buf,
 127                         int buf_size, void *data)
 128 {
 129     PutBitContext pb;
 130     AVFrame *p = data;
 131     int x, y;
 132
 133     p->pict_type = AV_PICTURE_TYPE_I;
 134     p->key_frame = 1;
 135
 136     init_put_bits(&pb, buf, buf_size / 8);
 137
 138     for (y = 0; y < avctx->height; y++) {
 139         uint8_t *luma = &p->data[0][y * p->linesize[0]];
 140         uint8_t *cb   = &p->data[1][y * p->linesize[1]];
 141         uint8_t *cr   = &p->data[2][y * p->linesize[2]];
 142         for (x = 0; x < avctx->width; x += 4) {
 143             put_bits(&pb, 5, luma[3] >> 3);
 144             put_bits(&pb, 5, luma[2] >> 3);
 145             put_bits(&pb, 5, luma[1] >> 3);
 146             put_bits(&pb, 5, luma[0] >> 3);
 147             luma += 4;
 148             put_bits(&pb, 6, *(cb++) >> 2);
 149             put_bits(&pb, 6, *(cr++) >> 2);
 150         }
 151     }
 152
 153     flush_put_bits(&pb);
 154
 155     return put_bits_count(&pb) / 8;
 156 }
 157
 158 AVCodec ff_cljr_encoder = {
 159     .name           = "cljr",
 160     .type           = AVMEDIA_TYPE_VIDEO,
 161     .id             = CODEC_ID_CLJR,
 162     .priv_data_size = sizeof(CLJRContext),
 163     .init           = common_init,
 164     .encode         = encode_frame,
 165     .pix_fmts       = (const enum PixelFormat[]) { PIX_FMT_YUV411P,
 166                                                    PIX_FMT_NONE },
 167     .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
 168 };
 169 #endif