cljr.c
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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 
27 #include "avcodec.h"
28 #include "get_bits.h"
29 #include "internal.h"
30 #include "put_bits.h"
31 
32 typedef struct CLJRContext {
34 } CLJRContext;
35 
37 {
38  CLJRContext * const a = avctx->priv_data;
39 
40  avctx->coded_frame = &a->picture;
41 
42  return 0;
43 }
44 
45 #if CONFIG_CLJR_DECODER
46 static int decode_frame(AVCodecContext *avctx,
47  void *data, int *got_frame,
48  AVPacket *avpkt)
49 {
50  const uint8_t *buf = avpkt->data;
51  int buf_size = avpkt->size;
52  CLJRContext * const a = avctx->priv_data;
53  GetBitContext gb;
54  AVFrame *picture = data;
55  AVFrame * const p = &a->picture;
56  int x, y;
57 
58  if (p->data[0])
59  avctx->release_buffer(avctx, p);
60 
61  if (avctx->height <= 0 || avctx->width <= 0) {
62  av_log(avctx, AV_LOG_ERROR, "Invalid width or height\n");
63  return AVERROR_INVALIDDATA;
64  }
65 
66  if (buf_size < avctx->height * avctx->width) {
67  av_log(avctx, AV_LOG_ERROR,
68  "Resolution larger than buffer size. Invalid header?\n");
69  return AVERROR_INVALIDDATA;
70  }
71 
72  p->reference = 0;
73  if (ff_get_buffer(avctx, p) < 0) {
74  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
75  return -1;
76  }
78  p->key_frame = 1;
79 
80  init_get_bits(&gb, buf, buf_size * 8);
81 
82  for (y = 0; y < avctx->height; y++) {
83  uint8_t *luma = &a->picture.data[0][y * a->picture.linesize[0]];
84  uint8_t *cb = &a->picture.data[1][y * a->picture.linesize[1]];
85  uint8_t *cr = &a->picture.data[2][y * a->picture.linesize[2]];
86  for (x = 0; x < avctx->width; x += 4) {
87  luma[3] = get_bits(&gb, 5) << 3;
88  luma[2] = get_bits(&gb, 5) << 3;
89  luma[1] = get_bits(&gb, 5) << 3;
90  luma[0] = get_bits(&gb, 5) << 3;
91  luma += 4;
92  *(cb++) = get_bits(&gb, 6) << 2;
93  *(cr++) = get_bits(&gb, 6) << 2;
94  }
95  }
96 
97  *picture = a->picture;
98  *got_frame = 1;
99 
100  return buf_size;
101 }
102 
103 static av_cold int decode_init(AVCodecContext *avctx)
104 {
105  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
106  return common_init(avctx);
107 }
108 
109 static av_cold int decode_end(AVCodecContext *avctx)
110 {
111  CLJRContext *a = avctx->priv_data;
112 
113  if (a->picture.data[0])
114  avctx->release_buffer(avctx, &a->picture);
115  return 0;
116 }
117 
118 AVCodec ff_cljr_decoder = {
119  .name = "cljr",
120  .type = AVMEDIA_TYPE_VIDEO,
121  .id = AV_CODEC_ID_CLJR,
122  .priv_data_size = sizeof(CLJRContext),
123  .init = decode_init,
124  .close = decode_end,
125  .decode = decode_frame,
126  .capabilities = CODEC_CAP_DR1,
127  .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
128 };
129 #endif
130 
131 #if CONFIG_CLJR_ENCODER
132 static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
133  const AVFrame *p, int *got_packet)
134 {
135  PutBitContext pb;
136  int x, y, ret;
137 
138  if ((ret = ff_alloc_packet(pkt, 32*avctx->height*avctx->width/4)) < 0) {
139  av_log(avctx, AV_LOG_ERROR, "Error getting output packet.\n");
140  return ret;
141  }
142 
144  avctx->coded_frame->key_frame = 1;
145 
146  init_put_bits(&pb, pkt->data, pkt->size);
147 
148  for (y = 0; y < avctx->height; y++) {
149  uint8_t *luma = &p->data[0][y * p->linesize[0]];
150  uint8_t *cb = &p->data[1][y * p->linesize[1]];
151  uint8_t *cr = &p->data[2][y * p->linesize[2]];
152  for (x = 0; x < avctx->width; x += 4) {
153  put_bits(&pb, 5, luma[3] >> 3);
154  put_bits(&pb, 5, luma[2] >> 3);
155  put_bits(&pb, 5, luma[1] >> 3);
156  put_bits(&pb, 5, luma[0] >> 3);
157  luma += 4;
158  put_bits(&pb, 6, *(cb++) >> 2);
159  put_bits(&pb, 6, *(cr++) >> 2);
160  }
161  }
162 
163  flush_put_bits(&pb);
164 
165  pkt->size = put_bits_count(&pb) / 8;
166  pkt->flags |= AV_PKT_FLAG_KEY;
167  *got_packet = 1;
168  return 0;
169 }
170 
171 AVCodec ff_cljr_encoder = {
172  .name = "cljr",
173  .type = AVMEDIA_TYPE_VIDEO,
174  .id = AV_CODEC_ID_CLJR,
175  .priv_data_size = sizeof(CLJRContext),
176  .init = common_init,
177  .encode2 = encode_frame,
178  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV411P,
179  AV_PIX_FMT_NONE },
180  .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
181 };
182 #endif