FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/mimic.c	Lines:	130	164	79.3 %
Date:	2021-01-26 11:44:58	Branches:	61	94	64.9 %


/*
 * Copyright (C) 2005  Ole André Vadla Ravnås <oleavr@gmail.com>
 * Copyright (C) 2008  Ramiro Polla
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * 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.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * 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
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

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

#include "libavutil/mem_internal.h"
#include "libavutil/thread.h"

#include "avcodec.h"
#include "blockdsp.h"
#include "internal.h"
#include "get_bits.h"
#include "bytestream.h"
#include "bswapdsp.h"
#include "hpeldsp.h"
#include "idctdsp.h"
#include "thread.h"

#define MIMIC_HEADER_SIZE   20
#define MIMIC_VLC_BITS      11

typedef struct MimicContext {
    AVCodecContext *avctx;

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

    void           *swap_buf;
    int             swap_buf_size;

    int             cur_index;
    int             prev_index;

    ThreadFrame     frames     [16];

    DECLARE_ALIGNED(32, int16_t, dct_block)[64];

    GetBitContext   gb;
    ScanTable       scantable;
    BlockDSPContext bdsp;
    BswapDSPContext bbdsp;
    HpelDSPContext  hdsp;
    IDCTDSPContext  idsp;

    /* Kept in the context so multithreading can have a constant to read from */
    int             next_cur_index;
    int             next_prev_index;
} MimicContext;

static VLC block_vlc;

static const uint8_t huffsyms[] = {
    0x10, 0x20, 0x30, 0x00, 0x11, 0x40, 0x50, 0x12, 0x13, 0x21, 0x31, 0x60,
    0x14, 0x15, 0x16, 0x22, 0x41, 0x17, 0x18, 0x23, 0x24, 0x25, 0x32, 0x42,
    0x51, 0x61, 0x70, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x26, 0x27,
    0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x33, 0x34, 0x35, 0x36, 0x37,
    0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x43, 0x44, 0x45, 0x46, 0x47,
    0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x52, 0x53, 0x54, 0x55, 0x56,
    0x57, 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x62, 0x63, 0x64, 0x65,
    0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x71, 0x72, 0x73,
    0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E,
};

static const uint8_t huffbits[] = {
     2,  2,  3,  4,  4,  4,  5,  5,  6,  6,  6,  6,  7,  7,  7,  7,  8,  8,
     8,  8,  9,  9,  9,  9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12,
    13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 17, 17,
    17, 17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21,
    22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
    26, 26, 27, 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,
    53, 60, 61, 54, 47, 55, 62, 63,
};

static av_cold int mimic_decode_end(AVCodecContext *avctx)
{
    MimicContext *ctx = avctx->priv_data;
    int i;

    av_freep(&ctx->swap_buf);
    ctx->swap_buf_size = 0;

    for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
        if (ctx->frames[i].f)
            ff_thread_release_buffer(avctx, &ctx->frames[i]);
        av_frame_free(&ctx->frames[i].f);
    }

    return 0;
}

static av_cold void mimic_init_static(void)
{
    INIT_VLC_STATIC_FROM_LENGTHS(&block_vlc, MIMIC_VLC_BITS, FF_ARRAY_ELEMS(huffbits),
                                 huffbits, 1, huffsyms, 1, 1, 0, 0, 4368);
}

static av_cold int mimic_decode_init(AVCodecContext *avctx)
{
    static AVOnce init_static_once = AV_ONCE_INIT;
    MimicContext *ctx = avctx->priv_data;
    int i;

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

    ff_blockdsp_init(&ctx->bdsp, avctx);
    ff_bswapdsp_init(&ctx->bbdsp);
    ff_hpeldsp_init(&ctx->hdsp, avctx->flags);
    ff_idctdsp_init(&ctx->idsp, avctx);
    ff_init_scantable(ctx->idsp.idct_permutation, &ctx->scantable, col_zag);

    for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
        ctx->frames[i].f = av_frame_alloc();
        if (!ctx->frames[i].f)
            return AVERROR(ENOMEM);
    }

    ff_thread_once(&init_static_once, mimic_init_static);

    return 0;
}

#if HAVE_THREADS
static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
{
    MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
    int i, ret;

    if (avctx == avctx_from)
        return 0;

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

    for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
        ff_thread_release_buffer(avctx, &dst->frames[i]);
        if (i != src->next_cur_index && src->frames[i].f->data[0]) {
            ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
            if (ret < 0)
                return ret;
        }
    }

    return 0;
}
#endif

static const int8_t vlcdec_lookup[9][64] = {
    {    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, },
};

static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
{
    int16_t *block = ctx->dct_block;
    unsigned int pos;

    ctx->bdsp.clear_block(block);

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

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

        vlc = get_vlc2(&ctx->gb, block_vlc.table, MIMIC_VLC_BITS, 3);
        if (!vlc) /* end-of-block code */
            return 0;
        if (vlc == -1)
            return AVERROR_INVALIDDATA;

        /* 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 AVERROR_INVALIDDATA;

        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 = ((int8_t*)vlcdec_lookup[num_bits])[value];
        if (pos < 3)
            coeff *= 16;
        else /* TODO Use >> 10 instead of / 1001 */
            coeff = (coeff * qscale) / 1001;

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

    return 0;
}

static int decode(MimicContext *ctx, int quality, int num_coeffs,
                  int is_iframe)
{
    int ret, y, x, plane, cur_row = 0;

    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->frames[ctx->cur_index ].f->linesize[plane];
        const uint8_t *src  = ctx->frames[ctx->prev_index].f->data[plane];
        uint8_t       *dst  = ctx->frames[ctx->cur_index ].f->data[plane];

        for (y = 0; y < ctx->num_vblocks[plane]; y++) {
            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)) {
                        if ((ret = vlc_decode_block(ctx, num_coeffs,
                                                    qscale)) < 0) {
                            av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
                                   "block.\n");
                            return ret;
                        }
                        ctx->idsp.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->frames[index].f->data[0];

                        if (index != ctx->cur_index && p) {
                            ff_thread_await_progress(&ctx->frames[index],
                                                     cur_row, 0);
                            p += src -
                                 ctx->frames[ctx->prev_index].f->data[plane];
                            ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
                        } else {
                            av_log(ctx->avctx, AV_LOG_ERROR,
                                     "No such backreference! Buggy sample.\n");
                        }
                    }
                } else {
                    ff_thread_await_progress(&ctx->frames[ctx->prev_index],
                                             cur_row, 0);
                    ctx->hdsp.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;

            ff_thread_report_progress(&ctx->frames[ctx->cur_index],
                                      cur_row++, 0);
        }
    }

    return 0;
}

/**
 * Flip the buffer upside-down and put it in the YVU order to revert the
 * way Mimic encodes frames.
 */
static void flip_swap_frame(AVFrame *f)
{
    int i;
    uint8_t *data_1 = f->data[1];
    f->data[0] = f->data[0] + ( f->height       - 1) * f->linesize[0];
    f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2];
    f->data[2] = data_1     + ((f->height >> 1) - 1) * f->linesize[1];
    for (i = 0; i < 3; i++)
        f->linesize[i] *= -1;
}

static int mimic_decode_frame(AVCodecContext *avctx, void *data,
                              int *got_frame, AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size       = avpkt->size;
    int swap_buf_size  = buf_size - MIMIC_HEADER_SIZE;
    MimicContext *ctx  = avctx->priv_data;
    GetByteContext gb;
    int is_pframe;
    int width, height;
    int quality, num_coeffs;
    int res;

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

    bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE);
    bytestream2_skip(&gb, 2); /* some constant (always 256) */
    quality    = bytestream2_get_le16u(&gb);
    width      = bytestream2_get_le16u(&gb);
    height     = bytestream2_get_le16u(&gb);
    bytestream2_skip(&gb, 4); /* some constant */
    is_pframe  = bytestream2_get_le32u(&gb);
    num_coeffs = bytestream2_get_byteu(&gb);
    bytestream2_skip(&gb, 3); /* some constant */

    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 AVERROR_INVALIDDATA;
        }

        res = ff_set_dimensions(avctx, width, height);
        if (res < 0)
            return res;

        ctx->avctx     = avctx;
        avctx->pix_fmt = AV_PIX_FMT_YUV420P;
        for (i = 0; i < 3; i++) {
            ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height,   3 + !!i);
            ctx->num_hblocks[i] =                width >> (3 + !!i);
        }
    } else if (width != ctx->avctx->width || height != ctx->avctx->height) {
        avpriv_request_sample(avctx, "Resolution changing");
        return AVERROR_PATCHWELCOME;
    }

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

    ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
    ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
                                                           AV_PICTURE_TYPE_I;
    if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
                                    AV_GET_BUFFER_FLAG_REF)) < 0)
        return res;

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

    ff_thread_finish_setup(avctx);

    av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size);
    if (!ctx->swap_buf)
        return AVERROR(ENOMEM);

    ctx->bbdsp.bswap_buf(ctx->swap_buf,
                         (const uint32_t *) (buf + MIMIC_HEADER_SIZE),
                         swap_buf_size >> 2);
    init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);

    res = decode(ctx, quality, num_coeffs, !is_pframe);
    ff_thread_report_progress(&ctx->frames[ctx->cur_index], INT_MAX, 0);
    if (res < 0) {
        if (!(avctx->active_thread_type & FF_THREAD_FRAME))
            ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
        return res;
    }

    if ((res = av_frame_ref(data, ctx->frames[ctx->cur_index].f)) < 0)
        return res;
    *got_frame      = 1;

    flip_swap_frame(data);

    ctx->prev_index = ctx->next_prev_index;
    ctx->cur_index  = ctx->next_cur_index;

    return buf_size;
}

AVCodec ff_mimic_decoder = {
    .name                  = "mimic",
    .long_name             = NULL_IF_CONFIG_SMALL("Mimic"),
    .type                  = AVMEDIA_TYPE_VIDEO,
    .id                    = AV_CODEC_ID_MIMIC,
    .priv_data_size        = sizeof(MimicContext),
    .init                  = mimic_decode_init,
    .close                 = mimic_decode_end,
    .decode                = mimic_decode_frame,
    .capabilities          = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
    .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
    .caps_internal         = FF_CODEC_CAP_ALLOCATE_PROGRESS |
                             FF_CODEC_CAP_INIT_CLEANUP | FF_CODEC_CAP_INIT_THREADSAFE,
};


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* Copyright (C) 2005 Ole André Vadla Ravnås <oleavr@gmail.com>
3			* Copyright (C) 2008 Ramiro Polla
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			#include <stdlib.h>
23			#include <string.h>
24			#include <stdint.h>
25
26			#include "libavutil/mem_internal.h"
27			#include "libavutil/thread.h"
28
29			#include "avcodec.h"
30			#include "blockdsp.h"
31			#include "internal.h"
32			#include "get_bits.h"
33			#include "bytestream.h"
34			#include "bswapdsp.h"
35			#include "hpeldsp.h"
36			#include "idctdsp.h"
37			#include "thread.h"
38
39			#define MIMIC_HEADER_SIZE 20
40			#define MIMIC_VLC_BITS 11
41
42			typedef struct MimicContext {
43			AVCodecContext *avctx;
44
45			int num_vblocks[3];
46			int num_hblocks[3];
47
48			void *swap_buf;
49			int swap_buf_size;
50
51			int cur_index;
52			int prev_index;
53
54			ThreadFrame frames [16];
55
56			DECLARE_ALIGNED(32, int16_t, dct_block)[64];
57
58			GetBitContext gb;
59			ScanTable scantable;
60			BlockDSPContext bdsp;
61			BswapDSPContext bbdsp;
62			HpelDSPContext hdsp;
63			IDCTDSPContext idsp;
64
65			/* Kept in the context so multithreading can have a constant to read from */
66			int next_cur_index;
67			int next_prev_index;
68			} MimicContext;
69
70			static VLC block_vlc;
71
72			static const uint8_t huffsyms[] = {
73			0x10, 0x20, 0x30, 0x00, 0x11, 0x40, 0x50, 0x12, 0x13, 0x21, 0x31, 0x60,
74			0x14, 0x15, 0x16, 0x22, 0x41, 0x17, 0x18, 0x23, 0x24, 0x25, 0x32, 0x42,
75			0x51, 0x61, 0x70, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x26, 0x27,
76			0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x33, 0x34, 0x35, 0x36, 0x37,
77			0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x43, 0x44, 0x45, 0x46, 0x47,
78			0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x52, 0x53, 0x54, 0x55, 0x56,
79			0x57, 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x62, 0x63, 0x64, 0x65,
80			0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x71, 0x72, 0x73,
81			0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E,
82			};
83
84			static const uint8_t huffbits[] = {
85			2, 2, 3, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8,
86			8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12,
87			13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 17, 17,
88			17, 17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21,
89			22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
90			26, 26, 27, 27, 27, 27, 28, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30,
91			};
92
93			static const uint8_t col_zag[64] = {
94			0, 8, 1, 2, 9, 16, 24, 17,
95			10, 3, 4, 11, 18, 25, 32, 40,
96			33, 26, 19, 12, 5, 6, 13, 20,
97			27, 34, 41, 48, 56, 49, 42, 35,
98			28, 21, 14, 7, 15, 22, 29, 36,
99			43, 50, 57, 58, 51, 44, 37, 30,
100			23, 31, 38, 45, 52, 59, 39, 46,
101			53, 60, 61, 54, 47, 55, 62, 63,
102			};
103
104		2	static av_cold int mimic_decode_end(AVCodecContext *avctx)
105			{
106		2	MimicContext *ctx = avctx->priv_data;
107			int i;
108
109		2	av_freep(&ctx->swap_buf);
110		2	ctx->swap_buf_size = 0;
111
112	✓✓	34	for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
113	✓✗	32	if (ctx->frames[i].f)
114		32	ff_thread_release_buffer(avctx, &ctx->frames[i]);
115		32	av_frame_free(&ctx->frames[i].f);
116			}
117
118		2	return 0;
119			}
120
121		1	static av_cold void mimic_init_static(void)
122			{
123		1	INIT_VLC_STATIC_FROM_LENGTHS(&block_vlc, MIMIC_VLC_BITS, FF_ARRAY_ELEMS(huffbits),
124			huffbits, 1, huffsyms, 1, 1, 0, 0, 4368);
125		1	}
126
127		2	static av_cold int mimic_decode_init(AVCodecContext *avctx)
128			{
129			static AVOnce init_static_once = AV_ONCE_INIT;
130		2	MimicContext *ctx = avctx->priv_data;
131			int i;
132
133		2	ctx->prev_index = 0;
134		2	ctx->cur_index = 15;
135
136		2	ff_blockdsp_init(&ctx->bdsp, avctx);
137		2	ff_bswapdsp_init(&ctx->bbdsp);
138		2	ff_hpeldsp_init(&ctx->hdsp, avctx->flags);
139		2	ff_idctdsp_init(&ctx->idsp, avctx);
140		2	ff_init_scantable(ctx->idsp.idct_permutation, &ctx->scantable, col_zag);
141
142	✓✓	34	for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
143		32	ctx->frames[i].f = av_frame_alloc();
144	✗✓	32	if (!ctx->frames[i].f)
145			return AVERROR(ENOMEM);
146			}
147
148		2	ff_thread_once(&init_static_once, mimic_init_static);
149
150		2	return 0;
151			}
152
153			#if HAVE_THREADS
154			static int mimic_decode_update_thread_context(AVCodecContext avctx, const AVCodecContext avctx_from)
155			{
156			MimicContext dst = avctx->priv_data, src = avctx_from->priv_data;
157			int i, ret;
158
159			if (avctx == avctx_from)
160			return 0;
161
162			dst->cur_index = src->next_cur_index;
163			dst->prev_index = src->next_prev_index;
164
165			for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
166			ff_thread_release_buffer(avctx, &dst->frames[i]);
167			if (i != src->next_cur_index && src->frames[i].f->data[0]) {
168			ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
169			if (ret < 0)
170			return ret;
171			}
172			}
173
174			return 0;
175			}
176			#endif
177
178			static const int8_t vlcdec_lookup[9][64] = {
179			{ 0, },
180			{ -1, 1, },
181			{ -3, 3, -2, 2, },
182			{ -7, 7, -6, 6, -5, 5, -4, 4, },
183			{ -15, 15, -14, 14, -13, 13, -12, 12,
184			-11, 11, -10, 10, -9, 9, -8, 8, },
185			{ -31, 31, -30, 30, -29, 29, -28, 28,
186			-27, 27, -26, 26, -25, 25, -24, 24,
187			-23, 23, -22, 22, -21, 21, -20, 20,
188			-19, 19, -18, 18, -17, 17, -16, 16, },
189			{ -63, 63, -62, 62, -61, 61, -60, 60,
190			-59, 59, -58, 58, -57, 57, -56, 56,
191			-55, 55, -54, 54, -53, 53, -52, 52,
192			-51, 51, -50, 50, -49, 49, -48, 48,
193			-47, 47, -46, 46, -45, 45, -44, 44,
194			-43, 43, -42, 42, -41, 41, -40, 40,
195			-39, 39, -38, 38, -37, 37, -36, 36,
196			-35, 35, -34, 34, -33, 33, -32, 32, },
197			{ -127, 127, -126, 126, -125, 125, -124, 124,
198			-123, 123, -122, 122, -121, 121, -120, 120,
199			-119, 119, -118, 118, -117, 117, -116, 116,
200			-115, 115, -114, 114, -113, 113, -112, 112,
201			-111, 111, -110, 110, -109, 109, -108, 108,
202			-107, 107, -106, 106, -105, 105, -104, 104,
203			-103, 103, -102, 102, -101, 101, -100, 100,
204			-99, 99, -98, 98, -97, 97, -96, 96, },
205			{ -95, 95, -94, 94, -93, 93, -92, 92,
206			-91, 91, -90, 90, -89, 89, -88, 88,
207			-87, 87, -86, 86, -85, 85, -84, 84,
208			-83, 83, -82, 82, -81, 81, -80, 80,
209			-79, 79, -78, 78, -77, 77, -76, 76,
210			-75, 75, -74, 74, -73, 73, -72, 72,
211			-71, 71, -70, 70, -69, 69, -68, 68,
212			-67, 67, -66, 66, -65, 65, -64, 64, },
213			};
214
215		44548	static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
216			{
217		44548	int16_t *block = ctx->dct_block;
218			unsigned int pos;
219
220		44548	ctx->bdsp.clear_block(block);
221
222		44548	block[0] = get_bits(&ctx->gb, 8) << 3;
223
224	✓✓	304893	for (pos = 1; pos < num_coeffs; pos++) {
225			uint32_t vlc, num_bits;
226			int value;
227			int coeff;
228
229		302169	vlc = get_vlc2(&ctx->gb, block_vlc.table, MIMIC_VLC_BITS, 3);
230	✓✓	302169	if (!vlc) /* end-of-block code */
231		41824	return 0;
232	✗✓	260345	if (vlc == -1)
233			return AVERROR_INVALIDDATA;
234
235			/* pos_add and num_bits are coded in the vlc code */
236		260345	pos += vlc & 15; // pos_add
237		260345	num_bits = vlc >> 4; // num_bits
238
239	✗✓	260345	if (pos >= 64)
240			return AVERROR_INVALIDDATA;
241
242		260345	value = get_bits(&ctx->gb, num_bits);
243
244			/* FFmpeg's IDCT behaves somewhat different from the original code, so
245			* a factor of 4 was added to the input */
246
247		260345	coeff = ((int8_t*)vlcdec_lookup[num_bits])[value];
248	✓✓	260345	if (pos < 3)
249		50048	coeff *= 16;
250			else /* TODO Use >> 10 instead of / 1001 */
251		210297	coeff = (coeff * qscale) / 1001;
252
253		260345	block[ctx->scantable.permutated[pos]] = coeff;
254			}
255
256		2724	return 0;
257			}
258
259		77	static int decode(MimicContext *ctx, int quality, int num_coeffs,
260			int is_iframe)
261			{
262		77	int ret, y, x, plane, cur_row = 0;
263
264	✓✓	308	for (plane = 0; plane < 3; plane++) {
265		231	const int is_chroma = !!plane;
266	✓✓	231	const int qscale = av_clip(10000 - quality, is_chroma ? 1000 : 2000,
267			10000) << 2;
268		231	const int stride = ctx->frames[ctx->cur_index ].f->linesize[plane];
269		231	const uint8_t *src = ctx->frames[ctx->prev_index].f->data[plane];
270		231	uint8_t *dst = ctx->frames[ctx->cur_index ].f->data[plane];
271
272	✓✓	4851	for (y = 0; y < ctx->num_vblocks[plane]; y++) {
273	✓✓	143220	for (x = 0; x < ctx->num_hblocks[plane]; x++) {
274			/* Check for a change condition in the current block.
275			* - iframes always change.
276			* - Luma plane changes on get_bits1 == 0
277			* - Chroma planes change on get_bits1 == 1 */
278	✓✓✓✓	138600	if (is_iframe \|\| get_bits1(&ctx->gb) == is_chroma) {
279			/* Luma planes may use a backreference from the 15 last
280			* frames preceding the previous. (get_bits1 == 1)
281			* Chroma planes don't use backreferences. */
282	✓✓✓✓ ✓✓	50491	if (is_chroma \|\| is_iframe \|\| !get_bits1(&ctx->gb)) {
283	✗✓	44548	if ((ret = vlc_decode_block(ctx, num_coeffs,
284			qscale)) < 0) {
285			av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
286			"block.\n");
287			return ret;
288			}
289		44548	ctx->idsp.idct_put(dst, stride, ctx->dct_block);
290			} else {
291		5943	unsigned int backref = get_bits(&ctx->gb, 4);
292		5943	int index = (ctx->cur_index + backref) & 15;
293		5943	uint8_t *p = ctx->frames[index].f->data[0];
294
295	✓✗✓✗	5943	if (index != ctx->cur_index && p) {
296		5943	ff_thread_await_progress(&ctx->frames[index],
297			cur_row, 0);
298		5943	p += src -
299		5943	ctx->frames[ctx->prev_index].f->data[plane];
300		5943	ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
301			} else {
302			av_log(ctx->avctx, AV_LOG_ERROR,
303			"No such backreference! Buggy sample.\n");
304			}
305			}
306			} else {
307		88109	ff_thread_await_progress(&ctx->frames[ctx->prev_index],
308			cur_row, 0);
309		88109	ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8);
310			}
311		138600	src += 8;
312		138600	dst += 8;
313			}
314		4620	src += (stride - ctx->num_hblocks[plane]) << 3;
315		4620	dst += (stride - ctx->num_hblocks[plane]) << 3;
316
317		4620	ff_thread_report_progress(&ctx->frames[ctx->cur_index],
318			cur_row++, 0);
319			}
320			}
321
322		77	return 0;
323			}
324
325			/**
326			* Flip the buffer upside-down and put it in the YVU order to revert the
327			* way Mimic encodes frames.
328			*/
329		77	static void flip_swap_frame(AVFrame *f)
330			{
331			int i;
332		77	uint8_t *data_1 = f->data[1];
333		77	f->data[0] = f->data[0] + ( f->height - 1) * f->linesize[0];
334		77	f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2];
335		77	f->data[2] = data_1 + ((f->height >> 1) - 1) * f->linesize[1];
336	✓✓	308	for (i = 0; i < 3; i++)
337		231	f->linesize[i] *= -1;
338		77	}
339
340		77	static int mimic_decode_frame(AVCodecContext avctx, void data,
341			int got_frame, AVPacket avpkt)
342			{
343		77	const uint8_t *buf = avpkt->data;
344		77	int buf_size = avpkt->size;
345		77	int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
346		77	MimicContext *ctx = avctx->priv_data;
347			GetByteContext gb;
348			int is_pframe;
349			int width, height;
350			int quality, num_coeffs;
351			int res;
352
353	✗✓	77	if (buf_size <= MIMIC_HEADER_SIZE) {
354			av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
355			return AVERROR_INVALIDDATA;
356			}
357
358		77	bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE);
359		77	bytestream2_skip(&gb, 2); /* some constant (always 256) */
360		77	quality = bytestream2_get_le16u(&gb);
361		77	width = bytestream2_get_le16u(&gb);
362		77	height = bytestream2_get_le16u(&gb);
363		77	bytestream2_skip(&gb, 4); /* some constant */
364		77	is_pframe = bytestream2_get_le32u(&gb);
365		77	num_coeffs = bytestream2_get_byteu(&gb);
366		77	bytestream2_skip(&gb, 3); /* some constant */
367
368	✓✓	77	if (!ctx->avctx) {
369			int i;
370
371	✗✓✗✗ ✓✗	2	if (!(width == 160 && height == 120) &&
372	✗✓	2	!(width == 320 && height == 240)) {
373			av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
374			return AVERROR_INVALIDDATA;
375			}
376
377		2	res = ff_set_dimensions(avctx, width, height);
378	✗✓	2	if (res < 0)
379			return res;
380
381		2	ctx->avctx = avctx;
382		2	avctx->pix_fmt = AV_PIX_FMT_YUV420P;
383	✓✓	8	for (i = 0; i < 3; i++) {
384	✓✓	6	ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height, 3 + !!i);
385	✓✓	6	ctx->num_hblocks[i] = width >> (3 + !!i);
386			}
387	✓✗✗✓	75	} else if (width != ctx->avctx->width \|\| height != ctx->avctx->height) {
388			avpriv_request_sample(avctx, "Resolution changing");
389			return AVERROR_PATCHWELCOME;
390			}
391
392	✓✓✗✓	77	if (is_pframe && !ctx->frames[ctx->prev_index].f->data[0]) {
393			av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
394			return AVERROR_INVALIDDATA;
395			}
396
397		77	ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
398	✓✓	77	ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
399			AV_PICTURE_TYPE_I;
400	✗✓	77	if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
401			AV_GET_BUFFER_FLAG_REF)) < 0)
402			return res;
403
404		77	ctx->next_prev_index = ctx->cur_index;
405		77	ctx->next_cur_index = (ctx->cur_index - 1) & 15;
406
407		77	ff_thread_finish_setup(avctx);
408
409		77	av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size);
410	✗✓	77	if (!ctx->swap_buf)
411			return AVERROR(ENOMEM);
412
413		77	ctx->bbdsp.bswap_buf(ctx->swap_buf,
414		77	(const uint32_t *) (buf + MIMIC_HEADER_SIZE),
415			swap_buf_size >> 2);
416		77	init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);
417
418		77	res = decode(ctx, quality, num_coeffs, !is_pframe);
419		77	ff_thread_report_progress(&ctx->frames[ctx->cur_index], INT_MAX, 0);
420	✗✓	77	if (res < 0) {
421			if (!(avctx->active_thread_type & FF_THREAD_FRAME))
422			ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
423			return res;
424			}
425
426	✗✓	77	if ((res = av_frame_ref(data, ctx->frames[ctx->cur_index].f)) < 0)
427			return res;
428		77	*got_frame = 1;
429
430		77	flip_swap_frame(data);
431
432		77	ctx->prev_index = ctx->next_prev_index;
433		77	ctx->cur_index = ctx->next_cur_index;
434
435		77	return buf_size;
436			}
437
438			AVCodec ff_mimic_decoder = {
439			.name = "mimic",
440			.long_name = NULL_IF_CONFIG_SMALL("Mimic"),
441			.type = AVMEDIA_TYPE_VIDEO,
442			.id = AV_CODEC_ID_MIMIC,
443			.priv_data_size = sizeof(MimicContext),
444			.init = mimic_decode_init,
445			.close = mimic_decode_end,
446			.decode = mimic_decode_frame,
447			.capabilities = AV_CODEC_CAP_DR1 \| AV_CODEC_CAP_FRAME_THREADS,
448			.update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
449			.caps_internal = FF_CODEC_CAP_ALLOCATE_PROGRESS \|
450			FF_CODEC_CAP_INIT_CLEANUP \| FF_CODEC_CAP_INIT_THREADSAFE,
451			};