Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / vble.c
CommitLineData
2ba45a60
DM
1/*
2 * VBLE Decoder
3 * Copyright (c) 2011 Derek Buitenhuis
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; 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 * VBLE Decoder
25 */
26
27#define BITSTREAM_READER_LE
28
29#include "avcodec.h"
30#include "get_bits.h"
31#include "huffyuvdsp.h"
32#include "internal.h"
33#include "mathops.h"
34
35typedef struct {
36 AVCodecContext *avctx;
37 HuffYUVDSPContext hdsp;
38
39 int size;
40 uint8_t *val; ///< This array first holds the lengths of vlc symbols and then their value.
41} VBLEContext;
42
43static int vble_unpack(VBLEContext *ctx, GetBitContext *gb)
44{
45 int i;
46 int allbits = 0;
47 static const uint8_t LUT[256] = {
48 8,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
49 5,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
50 6,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
51 5,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
52 7,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
53 5,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
54 6,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
55 5,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,
56 };
57
58 /* Read all the lengths in first */
59 for (i = 0; i < ctx->size; i++) {
60 /* At most we need to read 9 bits total to get indices up to 8 */
61 int val = show_bits(gb, 8);
62
63 // read reverse unary
64 if (val) {
65 val = LUT[val];
66 skip_bits(gb, val + 1);
67 ctx->val[i] = val;
68 } else {
69 skip_bits(gb, 8);
70 if (!get_bits1(gb))
71 return -1;
72 ctx->val[i] = 8;
73 }
74 allbits += ctx->val[i];
75 }
76
77 /* Check we have enough bits left */
78 if (get_bits_left(gb) < allbits)
79 return -1;
80 return 0;
81}
82
83static void vble_restore_plane(VBLEContext *ctx, AVFrame *pic,
84 GetBitContext *gb, int plane,
85 int offset, int width, int height)
86{
87 uint8_t *dst = pic->data[plane];
88 uint8_t *val = ctx->val + offset;
89 int stride = pic->linesize[plane];
90 int i, j, left, left_top;
91
92 for (i = 0; i < height; i++) {
93 for (j = 0; j < width; j++) {
94 /* get_bits can't take a length of 0 */
95 if (val[j]) {
96 int v = (1 << val[j]) + get_bits(gb, val[j]) - 1;
97 val[j] = (v >> 1) ^ -(v & 1);
98 }
99 }
100 if (i) {
101 left = 0;
102 left_top = dst[-stride];
103 ctx->hdsp.add_hfyu_median_pred(dst, dst - stride, val,
104 width, &left, &left_top);
105 } else {
106 dst[0] = val[0];
107 for (j = 1; j < width; j++)
108 dst[j] = val[j] + dst[j - 1];
109 }
110 dst += stride;
111 val += width;
112 }
113}
114
115static int vble_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
116 AVPacket *avpkt)
117{
118 VBLEContext *ctx = avctx->priv_data;
119 AVFrame *pic = data;
120 GetBitContext gb;
121 const uint8_t *src = avpkt->data;
122 int version;
123 int offset = 0;
124 int width_uv = avctx->width / 2, height_uv = avctx->height / 2;
125 int ret;
126
127 if (avpkt->size < 4 || avpkt->size - 4 > INT_MAX/8) {
128 av_log(avctx, AV_LOG_ERROR, "Invalid packet size\n");
129 return AVERROR_INVALIDDATA;
130 }
131
132 /* Allocate buffer */
133 if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
134 return ret;
135
136 /* Set flags */
137 pic->key_frame = 1;
138 pic->pict_type = AV_PICTURE_TYPE_I;
139
140 /* Version should always be 1 */
141 version = AV_RL32(src);
142
143 if (version != 1)
144 av_log(avctx, AV_LOG_WARNING, "Unsupported VBLE Version: %d\n", version);
145
146 init_get_bits(&gb, src + 4, (avpkt->size - 4) * 8);
147
148 /* Unpack */
149 if (vble_unpack(ctx, &gb) < 0) {
150 av_log(avctx, AV_LOG_ERROR, "Invalid Code\n");
151 return AVERROR_INVALIDDATA;
152 }
153
154 /* Restore planes. Should be almost identical to Huffyuv's. */
155 vble_restore_plane(ctx, pic, &gb, 0, offset, avctx->width, avctx->height);
156
157 /* Chroma */
158 if (!(ctx->avctx->flags & CODEC_FLAG_GRAY)) {
159 offset += avctx->width * avctx->height;
160 vble_restore_plane(ctx, pic, &gb, 1, offset, width_uv, height_uv);
161
162 offset += width_uv * height_uv;
163 vble_restore_plane(ctx, pic, &gb, 2, offset, width_uv, height_uv);
164 }
165
166 *got_frame = 1;
167
168 return avpkt->size;
169}
170
171static av_cold int vble_decode_close(AVCodecContext *avctx)
172{
173 VBLEContext *ctx = avctx->priv_data;
174 av_freep(&ctx->val);
175
176 return 0;
177}
178
179static av_cold int vble_decode_init(AVCodecContext *avctx)
180{
181 VBLEContext *ctx = avctx->priv_data;
182
183 /* Stash for later use */
184 ctx->avctx = avctx;
185 ff_huffyuvdsp_init(&ctx->hdsp);
186
187 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
188 avctx->bits_per_raw_sample = 8;
189
190 ctx->size = avpicture_get_size(avctx->pix_fmt,
191 avctx->width, avctx->height);
192
193 ctx->val = av_malloc_array(ctx->size, sizeof(*ctx->val));
194
195 if (!ctx->val) {
196 av_log(avctx, AV_LOG_ERROR, "Could not allocate values buffer.\n");
197 vble_decode_close(avctx);
198 return AVERROR(ENOMEM);
199 }
200
201 return 0;
202}
203
204AVCodec ff_vble_decoder = {
205 .name = "vble",
206 .long_name = NULL_IF_CONFIG_SMALL("VBLE Lossless Codec"),
207 .type = AVMEDIA_TYPE_VIDEO,
208 .id = AV_CODEC_ID_VBLE,
209 .priv_data_size = sizeof(VBLEContext),
210 .init = vble_decode_init,
211 .close = vble_decode_close,
212 .decode = vble_decode_frame,
213 .capabilities = CODEC_CAP_DR1,
214};