mimic.c 15.1 KB
Newer Older
Ramiro Polla's avatar
Ramiro Polla committed
1 2
/*
 * Copyright (C) 2005  Ole Andr Vadla Ravns <oleavr@gmail.com>
3
 * Copyright (C) 2008  Ramiro Polla
Ramiro Polla's avatar
Ramiro Polla committed
4
 *
5
 * This file is part of Libav.
Ramiro Polla's avatar
Ramiro Polla committed
6
 *
7
 * Libav is free software; you can redistribute it and/or
Ramiro Polla's avatar
Ramiro Polla committed
8 9 10 11
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
12
 * Libav is distributed in the hope that it will be useful,
Ramiro Polla's avatar
Ramiro Polla committed
13 14 15 16 17
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with Libav; if not, write to the Free Software
Ramiro Polla's avatar
Ramiro Polla committed
19 20 21 22 23 24 25 26
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <stdlib.h>
#include <string.h>
#include <stdint.h>

#include "avcodec.h"
27
#include "get_bits.h"
28
#include "bytestream.h"
Ramiro Polla's avatar
Ramiro Polla committed
29
#include "dsputil.h"
30
#include "thread.h"
Ramiro Polla's avatar
Ramiro Polla committed
31 32 33 34 35 36 37 38 39

#define MIMIC_HEADER_SIZE   20

typedef struct {
    AVCodecContext *avctx;

    int             num_vblocks[3];
    int             num_hblocks[3];

40
    void           *swap_buf;
Ramiro Polla's avatar
Ramiro Polla committed
41 42 43 44 45 46 47 48
    int             swap_buf_size;

    int             cur_index;
    int             prev_index;

    AVFrame         buf_ptrs    [16];
    AVPicture       flipped_ptrs[16];

49
    DECLARE_ALIGNED(16, DCTELEM, dct_block)[64];
Ramiro Polla's avatar
Ramiro Polla committed
50 51 52 53

    GetBitContext   gb;
    ScanTable       scantable;
    DSPContext      dsp;
Ramiro Polla's avatar
Ramiro Polla committed
54
    VLC             vlc;
55 56 57 58

    /* Kept in the context so multithreading can have a constant to read from */
    int             next_cur_index;
    int             next_prev_index;
Ramiro Polla's avatar
Ramiro Polla committed
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107
} MimicContext;

static const uint32_t huffcodes[] = {
    0x0000000a, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
    0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
    0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x0000000b,
    0x0000001b, 0x00000038, 0x00000078, 0x00000079, 0x0000007a, 0x000000f9,
    0x000000fa, 0x000003fb, 0x000007f8, 0x000007f9, 0x000007fa, 0x000007fb,
    0x00000ff8, 0x00000ff9, 0x00000001, 0x00000039, 0x0000007b, 0x000000fb,
    0x000001f8, 0x000001f9, 0x00000ffa, 0x00000ffb, 0x00001ff8, 0x00001ff9,
    0x00001ffa, 0x00001ffb, 0x00003ff8, 0x00003ff9, 0x00003ffa, 0x00000000,
    0x00000004, 0x0000003a, 0x000001fa, 0x00003ffb, 0x00007ff8, 0x00007ff9,
    0x00007ffa, 0x00007ffb, 0x0000fff8, 0x0000fff9, 0x0000fffa, 0x0000fffb,
    0x0001fff8, 0x0001fff9, 0x0001fffa, 0x00000000, 0x0000000c, 0x000000f8,
    0x000001fb, 0x0001fffb, 0x0003fff8, 0x0003fff9, 0x0003fffa, 0x0003fffb,
    0x0007fff8, 0x0007fff9, 0x0007fffa, 0x0007fffb, 0x000ffff8, 0x000ffff9,
    0x000ffffa, 0x00000000, 0x0000001a, 0x000003f8, 0x000ffffb, 0x001ffff8,
    0x001ffff9, 0x001ffffa, 0x001ffffb, 0x003ffff8, 0x003ffff9, 0x003ffffa,
    0x003ffffb, 0x007ffff8, 0x007ffff9, 0x007ffffa, 0x007ffffb, 0x00000000,
    0x0000003b, 0x000003f9, 0x00fffff8, 0x00fffff9, 0x00fffffa, 0x00fffffb,
    0x01fffff8, 0x01fffff9, 0x01fffffa, 0x01fffffb, 0x03fffff8, 0x03fffff9,
    0x03fffffa, 0x03fffffb, 0x07fffff8, 0x00000000, 0x000003fa, 0x07fffff9,
    0x07fffffa, 0x07fffffb, 0x0ffffff8, 0x0ffffff9, 0x0ffffffa, 0x0ffffffb,
    0x1ffffff8, 0x1ffffff9, 0x1ffffffa, 0x1ffffffb, 0x3ffffff8, 0x3ffffff9,
    0x3ffffffa,
};

static const uint8_t huffbits[] = {
     4,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
     0,  0,  0,  0,  2,  4,  5,  6,  7,  7,  7,  8,
     8, 10, 11, 11, 11, 11, 12, 12,  2,  6,  7,  8,
     9,  9, 12, 12, 13, 13, 13, 13, 14, 14, 14,  0,
     3,  6,  9, 14, 15, 15, 15, 15, 16, 16, 16, 16,
    17, 17, 17,  0,  4,  8,  9, 17, 18, 18, 18, 18,
    19, 19, 19, 19, 20, 20, 20,  0,  5, 10, 20, 21,
    21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23,  0,
     6, 10, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
    26, 26, 27,  0, 10, 27, 27, 27, 28, 28, 28, 28,
    29, 29, 29, 29, 30, 30, 30,
};

static const uint8_t col_zag[64] = {
     0,  8,  1,  2,  9, 16, 24, 17,
    10,  3,  4, 11, 18, 25, 32, 40,
    33, 26, 19, 12,  5,  6, 13, 20,
    27, 34, 41, 48, 56, 49, 42, 35,
    28, 21, 14,  7, 15, 22, 29, 36,
    43, 50, 57, 58, 51, 44, 37, 30,
    23, 31, 38, 45, 52, 59, 39, 46,
Ramiro Polla's avatar
Ramiro Polla committed
108
    53, 60, 61, 54, 47, 55, 62, 63,
Ramiro Polla's avatar
Ramiro Polla committed
109 110
};

111
static av_cold int mimic_decode_init(AVCodecContext *avctx)
Ramiro Polla's avatar
Ramiro Polla committed
112 113 114 115 116 117
{
    MimicContext *ctx = avctx->priv_data;

    ctx->prev_index = 0;
    ctx->cur_index = 15;

118
    if(init_vlc(&ctx->vlc, 11, FF_ARRAY_ELEMS(huffbits),
Ramiro Polla's avatar
Ramiro Polla committed
119 120 121 122 123 124 125 126 127 128
                 huffbits, 1, 1, huffcodes, 4, 4, 0)) {
        av_log(avctx, AV_LOG_ERROR, "error initializing vlc table\n");
        return -1;
    }
    dsputil_init(&ctx->dsp, avctx);
    ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable, col_zag);

    return 0;
}

129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145
static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
{
    MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;

    if (avctx == avctx_from) return 0;

    dst->cur_index  = src->next_cur_index;
    dst->prev_index = src->next_prev_index;

    memcpy(dst->buf_ptrs, src->buf_ptrs, sizeof(src->buf_ptrs));
    memcpy(dst->flipped_ptrs, src->flipped_ptrs, sizeof(src->flipped_ptrs));

    memset(&dst->buf_ptrs[dst->cur_index], 0, sizeof(AVFrame));

    return 0;
}

146
static const int8_t vlcdec_lookup[9][64] = {
Ramiro Polla's avatar
Ramiro Polla committed
147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182
    {    0, },
    {   -1,   1, },
    {   -3,   3,   -2,   2, },
    {   -7,   7,   -6,   6,   -5,   5,   -4,   4, },
    {  -15,  15,  -14,  14,  -13,  13,  -12,  12,
       -11,  11,  -10,  10,   -9,   9,   -8,   8, },
    {  -31,  31,  -30,  30,  -29,  29,  -28,  28,
       -27,  27,  -26,  26,  -25,  25,  -24,  24,
       -23,  23,  -22,  22,  -21,  21,  -20,  20,
       -19,  19,  -18,  18,  -17,  17,  -16,  16, },
    {  -63,  63,  -62,  62,  -61,  61,  -60,  60,
       -59,  59,  -58,  58,  -57,  57,  -56,  56,
       -55,  55,  -54,  54,  -53,  53,  -52,  52,
       -51,  51,  -50,  50,  -49,  49,  -48,  48,
       -47,  47,  -46,  46,  -45,  45,  -44,  44,
       -43,  43,  -42,  42,  -41,  41,  -40,  40,
       -39,  39,  -38,  38,  -37,  37,  -36,  36,
       -35,  35,  -34,  34,  -33,  33,  -32,  32, },
    { -127, 127, -126, 126, -125, 125, -124, 124,
      -123, 123, -122, 122, -121, 121, -120, 120,
      -119, 119, -118, 118, -117, 117, -116, 116,
      -115, 115, -114, 114, -113, 113, -112, 112,
      -111, 111, -110, 110, -109, 109, -108, 108,
      -107, 107, -106, 106, -105, 105, -104, 104,
      -103, 103, -102, 102, -101, 101, -100, 100,
       -99,  99,  -98,  98,  -97,  97,  -96,  96, },
    {  -95,  95,  -94,  94,  -93,  93,  -92,  92,
       -91,  91,  -90,  90,  -89,  89,  -88,  88,
       -87,  87,  -86,  86,  -85,  85,  -84,  84,
       -83,  83,  -82,  82,  -81,  81,  -80,  80,
       -79,  79,  -78,  78,  -77,  77,  -76,  76,
       -75,  75,  -74,  74,  -73,  73,  -72,  72,
       -71,  71,  -70,  70,  -69,  69,  -68,  68,
       -67,  67,  -66,  66,  -65,  65,  -64,  64, },
};

183
static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
Ramiro Polla's avatar
Ramiro Polla committed
184
{
185
    DCTELEM *block = ctx->dct_block;
Ramiro Polla's avatar
Ramiro Polla committed
186 187
    unsigned int pos;

Loren Merritt's avatar
Loren Merritt committed
188
    ctx->dsp.clear_block(block);
Ramiro Polla's avatar
Ramiro Polla committed
189 190 191 192 193 194 195 196

    block[0] = get_bits(&ctx->gb, 8) << 3;

    for(pos = 1; pos < num_coeffs; pos++) {
        uint32_t vlc, num_bits;
        int value;
        int coeff;

197
        vlc = get_vlc2(&ctx->gb, ctx->vlc.table, ctx->vlc.bits, 3);
Ramiro Polla's avatar
Ramiro Polla committed
198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229
        if(!vlc) /* end-of-block code */
            return 1;
        if(vlc == -1)
            return 0;

        /* pos_add and num_bits are coded in the vlc code */
        pos +=     vlc&15; // pos_add
        num_bits = vlc>>4; // num_bits

        if(pos >= 64)
            return 0;

        value = get_bits(&ctx->gb, num_bits);

        /* FFmpeg's IDCT behaves somewhat different from the original code, so
         * a factor of 4 was added to the input */

        coeff = vlcdec_lookup[num_bits][value];
        if(pos<3)
            coeff <<= 4;
        else /* TODO Use >> 10 instead of / 1001 */
            coeff = (coeff * qscale) / 1001;

        block[ctx->scantable.permutated[pos]] = coeff;
    }

    return 1;
}

static int decode(MimicContext *ctx, int quality, int num_coeffs,
                  int is_iframe)
{
230
    int y, x, plane, cur_row = 0;
Ramiro Polla's avatar
Ramiro Polla committed
231 232 233 234 235 236 237 238

    for(plane = 0; plane < 3; plane++) {
        const int is_chroma = !!plane;
        const int qscale = av_clip(10000-quality,is_chroma?1000:2000,10000)<<2;
        const int stride = ctx->flipped_ptrs[ctx->cur_index].linesize[plane];
        const uint8_t *src = ctx->flipped_ptrs[ctx->prev_index].data[plane];
        uint8_t       *dst = ctx->flipped_ptrs[ctx->cur_index ].data[plane];

Ramiro Polla's avatar
Ramiro Polla committed
239
        for(y = 0; y < ctx->num_vblocks[plane]; y++) {
Ramiro Polla's avatar
Ramiro Polla committed
240 241 242 243 244 245 246 247 248 249 250 251 252
            for(x = 0; x < ctx->num_hblocks[plane]; x++) {

                /* Check for a change condition in the current block.
                 * - iframes always change.
                 * - Luma plane changes on get_bits1 == 0
                 * - Chroma planes change on get_bits1 == 1 */
                if(is_iframe || get_bits1(&ctx->gb) == is_chroma) {

                    /* Luma planes may use a backreference from the 15 last
                     * frames preceding the previous. (get_bits1 == 1)
                     * Chroma planes don't use backreferences. */
                    if(is_chroma || is_iframe || !get_bits1(&ctx->gb)) {

253
                        if(!vlc_decode_block(ctx, num_coeffs, qscale))
Ramiro Polla's avatar
Ramiro Polla committed
254 255 256 257 258 259 260
                            return 0;
                        ctx->dsp.idct_put(dst, stride, ctx->dct_block);
                    } else {
                        unsigned int backref = get_bits(&ctx->gb, 4);
                        int index = (ctx->cur_index+backref)&15;
                        uint8_t *p = ctx->flipped_ptrs[index].data[0];

261
                        ff_thread_await_progress(&ctx->buf_ptrs[index], cur_row, 0);
Ramiro Polla's avatar
Ramiro Polla committed
262 263 264 265 266 267 268 269 270 271
                        if(p) {
                            p += src -
                                ctx->flipped_ptrs[ctx->prev_index].data[plane];
                            ctx->dsp.put_pixels_tab[1][0](dst, p, stride, 8);
                        } else {
                            av_log(ctx->avctx, AV_LOG_ERROR,
                                     "No such backreference! Buggy sample.\n");
                        }
                    }
                } else {
272
                    ff_thread_await_progress(&ctx->buf_ptrs[ctx->prev_index], cur_row, 0);
Ramiro Polla's avatar
Ramiro Polla committed
273 274 275 276 277 278 279
                    ctx->dsp.put_pixels_tab[1][0](dst, src, stride, 8);
                }
                src += 8;
                dst += 8;
            }
            src += (stride - ctx->num_hblocks[plane])<<3;
            dst += (stride - ctx->num_hblocks[plane])<<3;
280 281

            ff_thread_report_progress(&ctx->buf_ptrs[ctx->cur_index], cur_row++, 0);
Ramiro Polla's avatar
Ramiro Polla committed
282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297
        }
    }

    return 1;
}

/**
 * Flip the buffer upside-down and put it in the YVU order to match the
 * way Mimic encodes frames.
 */
static void prepare_avpic(MimicContext *ctx, AVPicture *dst, AVPicture *src)
{
    int i;
    dst->data[0] = src->data[0]+( ctx->avctx->height    -1)*src->linesize[0];
    dst->data[1] = src->data[2]+((ctx->avctx->height>>1)-1)*src->linesize[2];
    dst->data[2] = src->data[1]+((ctx->avctx->height>>1)-1)*src->linesize[1];
Ramiro Polla's avatar
Ramiro Polla committed
298
    for(i = 0; i < 3; i++)
Ramiro Polla's avatar
Ramiro Polla committed
299 300 301 302
        dst->linesize[i] = -src->linesize[i];
}

static int mimic_decode_frame(AVCodecContext *avctx, void *data,
303
                              int *data_size, AVPacket *avpkt)
Ramiro Polla's avatar
Ramiro Polla committed
304
{
305 306
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
Ramiro Polla's avatar
Ramiro Polla committed
307 308 309 310 311 312 313 314 315 316 317
    MimicContext *ctx = avctx->priv_data;
    int is_pframe;
    int width, height;
    int quality, num_coeffs;
    int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;

    if(buf_size < MIMIC_HEADER_SIZE) {
        av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
        return -1;
    }

318
    buf       += 2; /* some constant (always 256) */
319 320 321
    quality    = bytestream_get_le16(&buf);
    width      = bytestream_get_le16(&buf);
    height     = bytestream_get_le16(&buf);
322
    buf       += 4; /* some constant */
323
    is_pframe  = bytestream_get_le32(&buf);
324 325
    num_coeffs = bytestream_get_byte(&buf);
    buf       += 3; /* some constant */
Ramiro Polla's avatar
Ramiro Polla committed
326 327 328 329 330 331 332 333 334 335 336 337 338 339

    if(!ctx->avctx) {
        int i;

        if(!(width == 160 && height == 120) &&
           !(width == 320 && height == 240)) {
            av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
            return -1;
        }

        ctx->avctx     = avctx;
        avctx->width   = width;
        avctx->height  = height;
        avctx->pix_fmt = PIX_FMT_YUV420P;
Ramiro Polla's avatar
Ramiro Polla committed
340
        for(i = 0; i < 3; i++) {
Ramiro Polla's avatar
Ramiro Polla committed
341 342 343 344 345 346 347 348 349 350 351 352 353 354
            ctx->num_vblocks[i] = -((-height) >> (3 + !!i));
            ctx->num_hblocks[i] =     width   >> (3 + !!i) ;
        }
    } else if(width != ctx->avctx->width || height != ctx->avctx->height) {
        av_log(avctx, AV_LOG_ERROR, "resolution changing is not supported\n");
        return -1;
    }

    if(is_pframe && !ctx->buf_ptrs[ctx->prev_index].data[0]) {
        av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
        return -1;
    }

    ctx->buf_ptrs[ctx->cur_index].reference = 1;
355 356
    ctx->buf_ptrs[ctx->cur_index].pict_type = is_pframe ? FF_P_TYPE:FF_I_TYPE;
    if(ff_thread_get_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index])) {
Ramiro Polla's avatar
Ramiro Polla committed
357 358 359 360
        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
        return -1;
    }

361 362 363
    ctx->next_prev_index = ctx->cur_index;
    ctx->next_cur_index  = (ctx->cur_index - 1) & 15;

Ramiro Polla's avatar
Ramiro Polla committed
364 365 366
    prepare_avpic(ctx, &ctx->flipped_ptrs[ctx->cur_index],
                  (AVPicture*) &ctx->buf_ptrs[ctx->cur_index]);

367 368
    ff_thread_finish_setup(avctx);

369
    av_fast_malloc(&ctx->swap_buf, &ctx->swap_buf_size,
Ramiro Polla's avatar
Ramiro Polla committed
370 371
                                 swap_buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
    if(!ctx->swap_buf)
372
        return AVERROR(ENOMEM);
Ramiro Polla's avatar
Ramiro Polla committed
373

374
    ctx->dsp.bswap_buf(ctx->swap_buf,
375
                        (const uint32_t*) buf,
Ramiro Polla's avatar
Ramiro Polla committed
376 377 378 379
                        swap_buf_size>>2);
    init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);

    if(!decode(ctx, quality, num_coeffs, !is_pframe)) {
380 381 382 383 384 385
        if (avctx->active_thread_type&FF_THREAD_FRAME)
            ff_thread_report_progress(&ctx->buf_ptrs[ctx->cur_index], INT_MAX, 0);
        else {
            ff_thread_release_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index]);
            return -1;
        }
Ramiro Polla's avatar
Ramiro Polla committed
386 387 388 389 390
    }

    *(AVFrame*)data = ctx->buf_ptrs[ctx->cur_index];
    *data_size = sizeof(AVFrame);

391 392
    ctx->prev_index = ctx->next_prev_index;
    ctx->cur_index  = ctx->next_cur_index;
Ramiro Polla's avatar
Ramiro Polla committed
393 394 395

    /* Only release frames that aren't used for backreferences anymore */
    if(ctx->buf_ptrs[ctx->cur_index].data[0])
396
        ff_thread_release_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index]);
Ramiro Polla's avatar
Ramiro Polla committed
397 398 399 400

    return buf_size;
}

401
static av_cold int mimic_decode_end(AVCodecContext *avctx)
Ramiro Polla's avatar
Ramiro Polla committed
402 403 404 405 406
{
    MimicContext *ctx = avctx->priv_data;
    int i;

    av_free(ctx->swap_buf);
407 408 409

    if(avctx->is_copy) return 0;

Ramiro Polla's avatar
Ramiro Polla committed
410 411
    for(i = 0; i < 16; i++)
        if(ctx->buf_ptrs[i].data[0])
412
            ff_thread_release_buffer(avctx, &ctx->buf_ptrs[i]);
Ramiro Polla's avatar
Ramiro Polla committed
413
    free_vlc(&ctx->vlc);
Ramiro Polla's avatar
Ramiro Polla committed
414 415 416 417

    return 0;
}

418
AVCodec ff_mimic_decoder = {
Ramiro Polla's avatar
Ramiro Polla committed
419
    "mimic",
420
    AVMEDIA_TYPE_VIDEO,
Ramiro Polla's avatar
Ramiro Polla committed
421 422 423 424 425 426
    CODEC_ID_MIMIC,
    sizeof(MimicContext),
    mimic_decode_init,
    NULL,
    mimic_decode_end,
    mimic_decode_frame,
427
    CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
428
    .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
429
    .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context)
Ramiro Polla's avatar
Ramiro Polla committed
430
};