1/*
2 * Fraps FPS1 decoder
3 * Copyright (c) 2005 Roine Gustafsson
4 * Copyright (c) 2006 Konstantin Shishkov
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file
25 * Lossless Fraps 'FPS1' decoder
26 * @author Roine Gustafsson <roine at users sf net>
27 * @author Konstantin Shishkov
28 *
29 * Codec algorithm for version 0 is taken from Transcode <www.transcoding.org>
30 *
31 * Version 2 files support by Konstantin Shishkov
32 */
33
34#include "avcodec.h"
35#include "get_bits.h"
36#include "huffman.h"
37#include "bytestream.h"
38#include "dsputil.h"
39
40#define FPS_TAG MKTAG('F', 'P', 'S', 'x')
41
42/**
43 * local variable storage
44 */
45typedef struct FrapsContext{
46    AVCodecContext *avctx;
47    AVFrame frame;
48    uint8_t *tmpbuf;
49    DSPContext dsp;
50} FrapsContext;
51
52
53/**
54 * initializes decoder
55 * @param avctx codec context
56 * @return 0 on success or negative if fails
57 */
58static av_cold int decode_init(AVCodecContext *avctx)
59{
60    FrapsContext * const s = avctx->priv_data;
61
62    avctx->coded_frame = (AVFrame*)&s->frame;
63    avctx->pix_fmt= PIX_FMT_NONE; /* set in decode_frame */
64
65    s->avctx = avctx;
66    s->tmpbuf = NULL;
67
68    dsputil_init(&s->dsp, avctx);
69
70    return 0;
71}
72
73/**
74 * Comparator - our nodes should ascend by count
75 * but with preserved symbol order
76 */
77static int huff_cmp(const void *va, const void *vb){
78    const Node *a = va, *b = vb;
79    return (a->count - b->count)*256 + a->sym - b->sym;
80}
81
82/**
83 * decode Fraps v2 packed plane
84 */
85static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
86                               int h, const uint8_t *src, int size, int Uoff,
87                               const int step)
88{
89    int i, j;
90    GetBitContext gb;
91    VLC vlc;
92    Node nodes[512];
93
94    for(i = 0; i < 256; i++)
95        nodes[i].count = bytestream_get_le32(&src);
96    size -= 1024;
97    if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp,
98                           FF_HUFFMAN_FLAG_ZERO_COUNT) < 0)
99        return -1;
100    /* we have built Huffman table and are ready to decode plane */
101
102    /* convert bits so they may be used by standard bitreader */
103    s->dsp.bswap_buf((uint32_t *)s->tmpbuf, (const uint32_t *)src, size >> 2);
104
105    init_get_bits(&gb, s->tmpbuf, size * 8);
106    for(j = 0; j < h; j++){
107        for(i = 0; i < w*step; i += step){
108            dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
109            /* lines are stored as deltas between previous lines
110             * and we need to add 0x80 to the first lines of chroma planes
111             */
112            if(j) dst[i] += dst[i - stride];
113            else if(Uoff) dst[i] += 0x80;
114        }
115        dst += stride;
116    }
117    free_vlc(&vlc);
118    return 0;
119}
120
121/**
122 * decode a frame
123 * @param avctx codec context
124 * @param data output AVFrame
125 * @param data_size size of output data or 0 if no picture is returned
126 * @param buf input data frame
127 * @param buf_size size of input data frame
128 * @return number of consumed bytes on success or negative if decode fails
129 */
130static int decode_frame(AVCodecContext *avctx,
131                        void *data, int *data_size,
132                        AVPacket *avpkt)
133{
134    const uint8_t *buf = avpkt->data;
135    int buf_size = avpkt->size;
136    FrapsContext * const s = avctx->priv_data;
137    AVFrame *frame = data;
138    AVFrame * const f = (AVFrame*)&s->frame;
139    uint32_t header;
140    unsigned int version,header_size;
141    unsigned int x, y;
142    const uint32_t *buf32;
143    uint32_t *luma1,*luma2,*cb,*cr;
144    uint32_t offs[4];
145    int i, j, is_chroma, planes;
146
147
148    header = AV_RL32(buf);
149    version = header & 0xff;
150    header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
151
152    if (version > 5) {
153        av_log(avctx, AV_LOG_ERROR,
154               "This file is encoded with Fraps version %d. " \
155               "This codec can only decode versions <= 5.\n", version);
156        return -1;
157    }
158
159    buf+=4;
160    if (header_size == 8)
161        buf+=4;
162
163    switch(version) {
164    case 0:
165    default:
166        /* Fraps v0 is a reordered YUV420 */
167        avctx->pix_fmt = PIX_FMT_YUV420P;
168
169        if ( (buf_size != avctx->width*avctx->height*3/2+header_size) &&
170             (buf_size != header_size) ) {
171            av_log(avctx, AV_LOG_ERROR,
172                   "Invalid frame length %d (should be %d)\n",
173                   buf_size, avctx->width*avctx->height*3/2+header_size);
174            return -1;
175        }
176
177        if (( (avctx->width % 8) != 0) || ( (avctx->height % 2) != 0 )) {
178            av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
179                   avctx->width, avctx->height);
180            return -1;
181        }
182
183        f->reference = 1;
184        f->buffer_hints = FF_BUFFER_HINTS_VALID |
185                          FF_BUFFER_HINTS_PRESERVE |
186                          FF_BUFFER_HINTS_REUSABLE;
187        if (avctx->reget_buffer(avctx, f)) {
188            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
189            return -1;
190        }
191        /* bit 31 means same as previous pic */
192        f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
193        f->key_frame = f->pict_type == FF_I_TYPE;
194
195        if (f->pict_type == FF_I_TYPE) {
196            buf32=(const uint32_t*)buf;
197            for(y=0; y<avctx->height/2; y++){
198                luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
199                luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
200                cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
201                cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
202                for(x=0; x<avctx->width; x+=8){
203                    *(luma1++) = *(buf32++);
204                    *(luma1++) = *(buf32++);
205                    *(luma2++) = *(buf32++);
206                    *(luma2++) = *(buf32++);
207                    *(cr++) = *(buf32++);
208                    *(cb++) = *(buf32++);
209                }
210            }
211        }
212        break;
213
214    case 1:
215        /* Fraps v1 is an upside-down BGR24 */
216        avctx->pix_fmt = PIX_FMT_BGR24;
217
218        if ( (buf_size != avctx->width*avctx->height*3+header_size) &&
219             (buf_size != header_size) ) {
220            av_log(avctx, AV_LOG_ERROR,
221                   "Invalid frame length %d (should be %d)\n",
222                   buf_size, avctx->width*avctx->height*3+header_size);
223            return -1;
224        }
225
226        f->reference = 1;
227        f->buffer_hints = FF_BUFFER_HINTS_VALID |
228                          FF_BUFFER_HINTS_PRESERVE |
229                          FF_BUFFER_HINTS_REUSABLE;
230        if (avctx->reget_buffer(avctx, f)) {
231            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
232            return -1;
233        }
234        /* bit 31 means same as previous pic */
235        f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
236        f->key_frame = f->pict_type == FF_I_TYPE;
237
238        if (f->pict_type == FF_I_TYPE) {
239            for(y=0; y<avctx->height; y++)
240                memcpy(&f->data[0][ (avctx->height-y)*f->linesize[0] ],
241                       &buf[y*avctx->width*3],
242                       3*avctx->width);
243        }
244        break;
245
246    case 2:
247    case 4:
248        /**
249         * Fraps v2 is Huffman-coded YUV420 planes
250         * Fraps v4 is virtually the same
251         */
252        avctx->pix_fmt = PIX_FMT_YUV420P;
253        planes = 3;
254        f->reference = 1;
255        f->buffer_hints = FF_BUFFER_HINTS_VALID |
256                          FF_BUFFER_HINTS_PRESERVE |
257                          FF_BUFFER_HINTS_REUSABLE;
258        if (avctx->reget_buffer(avctx, f)) {
259            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
260            return -1;
261        }
262        /* skip frame */
263        if(buf_size == 8) {
264            f->pict_type = FF_P_TYPE;
265            f->key_frame = 0;
266            break;
267        }
268        f->pict_type = FF_I_TYPE;
269        f->key_frame = 1;
270        if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
271            av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
272            return -1;
273        }
274        for(i = 0; i < planes; i++) {
275            offs[i] = AV_RL32(buf + 4 + i * 4);
276            if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
277                av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
278                return -1;
279            }
280        }
281        offs[planes] = buf_size;
282        for(i = 0; i < planes; i++){
283            is_chroma = !!i;
284            s->tmpbuf = av_realloc(s->tmpbuf, offs[i + 1] - offs[i] - 1024 + FF_INPUT_BUFFER_PADDING_SIZE);
285            if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
286                    avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma, 1) < 0) {
287                av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
288                return -1;
289            }
290        }
291        break;
292    case 3:
293    case 5:
294        /* Virtually the same as version 4, but is for RGB24 */
295        avctx->pix_fmt = PIX_FMT_BGR24;
296        planes = 3;
297        f->reference = 1;
298        f->buffer_hints = FF_BUFFER_HINTS_VALID |
299                          FF_BUFFER_HINTS_PRESERVE |
300                          FF_BUFFER_HINTS_REUSABLE;
301        if (avctx->reget_buffer(avctx, f)) {
302            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
303            return -1;
304        }
305        /* skip frame */
306        if(buf_size == 8) {
307            f->pict_type = FF_P_TYPE;
308            f->key_frame = 0;
309            break;
310        }
311        f->pict_type = FF_I_TYPE;
312        f->key_frame = 1;
313        if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
314            av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
315            return -1;
316        }
317        for(i = 0; i < planes; i++) {
318            offs[i] = AV_RL32(buf + 4 + i * 4);
319            if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
320                av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
321                return -1;
322            }
323        }
324        offs[planes] = buf_size;
325        for(i = 0; i < planes; i++){
326            s->tmpbuf = av_realloc(s->tmpbuf, offs[i + 1] - offs[i] - 1024 + FF_INPUT_BUFFER_PADDING_SIZE);
327            if(fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)), -f->linesize[0],
328                    avctx->width, avctx->height, buf + offs[i], offs[i + 1] - offs[i], 0, 3) < 0) {
329                av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
330                return -1;
331            }
332        }
333        // convert pseudo-YUV into real RGB
334        for(j = 0; j < avctx->height; j++){
335            for(i = 0; i < avctx->width; i++){
336                f->data[0][0 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
337                f->data[0][2 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
338            }
339        }
340        break;
341    }
342
343    *frame = *f;
344    *data_size = sizeof(AVFrame);
345
346    return buf_size;
347}
348
349
350/**
351 * closes decoder
352 * @param avctx codec context
353 * @return 0 on success or negative if fails
354 */
355static av_cold int decode_end(AVCodecContext *avctx)
356{
357    FrapsContext *s = (FrapsContext*)avctx->priv_data;
358
359    if (s->frame.data[0])
360        avctx->release_buffer(avctx, &s->frame);
361
362    av_freep(&s->tmpbuf);
363    return 0;
364}
365
366
367AVCodec fraps_decoder = {
368    "fraps",
369    AVMEDIA_TYPE_VIDEO,
370    CODEC_ID_FRAPS,
371    sizeof(FrapsContext),
372    decode_init,
373    NULL,
374    decode_end,
375    decode_frame,
376    CODEC_CAP_DR1,
377    .long_name = NULL_IF_CONFIG_SMALL("Fraps"),
378};
379