xref: /third_party/ffmpeg/libavcodec/eatgq.c (revision cabdff1a)
1/*
2 * Electronic Arts TGQ Video Decoder
3 * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
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 St, Fifth Floor, Boston, MA  02110-1301  USA
20 */
21
22/**
23 * @file
24 * Electronic Arts TGQ Video Decoder
25 * @author Peter Ross <pross@xvid.org>
26 *
27 * Technical details here:
28 * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
29 */
30
31#define BITSTREAM_READER_LE
32
33#include "libavutil/mem_internal.h"
34
35#include "aandcttab.h"
36#include "avcodec.h"
37#include "bytestream.h"
38#include "codec_internal.h"
39#include "eaidct.h"
40#include "get_bits.h"
41#include "idctdsp.h"
42#include "internal.h"
43
44typedef struct TgqContext {
45    AVCodecContext *avctx;
46    int width, height;
47    ScanTable scantable;
48    int qtable[64];
49    DECLARE_ALIGNED(16, int16_t, block)[6][64];
50    GetByteContext gb;
51} TgqContext;
52
53static av_cold int tgq_decode_init(AVCodecContext *avctx)
54{
55    TgqContext *s = avctx->priv_data;
56    uint8_t idct_permutation[64];
57    s->avctx = avctx;
58    ff_init_scantable_permutation(idct_permutation, FF_IDCT_PERM_NONE);
59    ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
60    avctx->framerate = (AVRational){ 15, 1 };
61    avctx->pix_fmt   = AV_PIX_FMT_YUV420P;
62    return 0;
63}
64
65static int tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
66{
67    uint8_t *perm = s->scantable.permutated;
68    int i, j, value;
69    block[0] = get_sbits(gb, 8) * s->qtable[0];
70    for (i = 1; i < 64;) {
71        switch (show_bits(gb, 3)) {
72        case 4:
73            if (i >= 63)
74                return AVERROR_INVALIDDATA;
75            block[perm[i++]] = 0;
76        case 0:
77            block[perm[i++]] = 0;
78            skip_bits(gb, 3);
79            break;
80        case 5:
81        case 1:
82            skip_bits(gb, 2);
83            value = get_bits(gb, 6);
84            if (value > 64 - i)
85                return AVERROR_INVALIDDATA;
86            for (j = 0; j < value; j++)
87                block[perm[i++]] = 0;
88            break;
89        case 6:
90            skip_bits(gb, 3);
91            block[perm[i]] = -s->qtable[perm[i]];
92            i++;
93            break;
94        case 2:
95            skip_bits(gb, 3);
96            block[perm[i]] = s->qtable[perm[i]];
97            i++;
98            break;
99        case 7: // 111b
100        case 3: // 011b
101            skip_bits(gb, 2);
102            if (show_bits(gb, 6) == 0x3F) {
103                skip_bits(gb, 6);
104                block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
105            } else {
106                block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
107            }
108            i++;
109            break;
110        }
111    }
112    block[0] += 128 << 4;
113    return 0;
114}
115
116static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
117                            int mb_x, int mb_y)
118{
119    ptrdiff_t linesize = frame->linesize[0];
120    uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)           + mb_x * 16;
121    uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
122    uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
123
124    ff_ea_idct_put_c(dest_y                   , linesize, block[0]);
125    ff_ea_idct_put_c(dest_y                + 8, linesize, block[1]);
126    ff_ea_idct_put_c(dest_y + 8 * linesize    , linesize, block[2]);
127    ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
128    if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
129         ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
130         ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
131    }
132}
133
134static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
135                              ptrdiff_t dst_stride, int dc)
136{
137    int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
138    int j;
139    for (j = 0; j < 8; j++)
140        memset(dst + j * dst_stride, level, 8);
141}
142
143static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame,
144                                   int mb_x, int mb_y, const int8_t *dc)
145{
146    ptrdiff_t linesize = frame->linesize[0];
147    uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
148    uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
149    uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
150    tgq_dconly(s, dest_y,                    linesize, dc[0]);
151    tgq_dconly(s, dest_y                + 8, linesize, dc[1]);
152    tgq_dconly(s, dest_y + 8 * linesize,     linesize, dc[2]);
153    tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
154    if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
155        tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
156        tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
157    }
158}
159
160static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
161{
162    int mode;
163    int i;
164    int8_t dc[6];
165
166    mode = bytestream2_get_byte(&s->gb);
167    if (mode > 12) {
168        GetBitContext gb;
169        int ret = init_get_bits8(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode));
170        if (ret < 0)
171            return ret;
172
173        for (i = 0; i < 6; i++) {
174            int ret = tgq_decode_block(s, s->block[i], &gb);
175            if (ret < 0)
176                return ret;
177        }
178        tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
179        bytestream2_skip(&s->gb, mode);
180    } else {
181        if (mode == 3) {
182            memset(dc, bytestream2_get_byte(&s->gb), 4);
183            dc[4] = bytestream2_get_byte(&s->gb);
184            dc[5] = bytestream2_get_byte(&s->gb);
185        } else if (mode == 6) {
186            bytestream2_get_buffer(&s->gb, dc, 6);
187        } else if (mode == 12) {
188            for (i = 0; i < 6; i++) {
189                dc[i] = bytestream2_get_byte(&s->gb);
190                bytestream2_skip(&s->gb, 1);
191            }
192        } else {
193            av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
194            return -1;
195        }
196        tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
197    }
198    return 0;
199}
200
201static void tgq_calculate_qtable(TgqContext *s, int quant)
202{
203    int i, j;
204    const int a = (14 * (100 - quant)) / 100 + 1;
205    const int b = (11 * (100 - quant)) / 100 + 4;
206    for (j = 0; j < 8; j++)
207        for (i = 0; i < 8; i++)
208            s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
209                                    ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
210}
211
212static int tgq_decode_frame(AVCodecContext *avctx, AVFrame *frame,
213                            int *got_frame, AVPacket *avpkt)
214{
215    const uint8_t *buf = avpkt->data;
216    int buf_size       = avpkt->size;
217    TgqContext *s      = avctx->priv_data;
218    int x, y, ret;
219    int big_endian;
220
221    if (buf_size < 16) {
222        av_log(avctx, AV_LOG_WARNING, "truncated header\n");
223        return AVERROR_INVALIDDATA;
224    }
225    big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
226    bytestream2_init(&s->gb, buf + 8, buf_size - 8);
227    if (big_endian) {
228        s->width  = bytestream2_get_be16u(&s->gb);
229        s->height = bytestream2_get_be16u(&s->gb);
230    } else {
231        s->width  = bytestream2_get_le16u(&s->gb);
232        s->height = bytestream2_get_le16u(&s->gb);
233    }
234
235    ret = ff_set_dimensions(s->avctx, s->width, s->height);
236    if (ret < 0)
237        return ret;
238
239    tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
240    bytestream2_skip(&s->gb, 3);
241
242    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
243        return ret;
244    frame->key_frame = 1;
245    frame->pict_type = AV_PICTURE_TYPE_I;
246
247    for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
248        for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
249            if (tgq_decode_mb(s, frame, y, x) < 0)
250                return AVERROR_INVALIDDATA;
251
252    *got_frame = 1;
253
254    return avpkt->size;
255}
256
257const FFCodec ff_eatgq_decoder = {
258    .p.name         = "eatgq",
259    .p.long_name    = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
260    .p.type         = AVMEDIA_TYPE_VIDEO,
261    .p.id           = AV_CODEC_ID_TGQ,
262    .priv_data_size = sizeof(TgqContext),
263    .init           = tgq_decode_init,
264    FF_CODEC_DECODE_CB(tgq_decode_frame),
265    .p.capabilities = AV_CODEC_CAP_DR1,
266    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
267};
268