FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/tdsc.c	Lines:	252	322	78.3 %
Date:	2020-08-14 10:39:37	Branches:	110	182	60.4 %


/*
 * TDSC decoder
 * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
 *
 * 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
 */

/**
 * @file
 * TDSC decoder
 *
 * Fourcc: TSDC
 *
 * TDSC is very simple. It codes picture by tiles, storing them in raw BGR24
 * format or compressing them in JPEG. Frames can be full pictures or just
 * updates to the previous frame. Cursor is found in its own frame or at the
 * bottom of the picture. Every frame is then packed with zlib.
 *
 * Supports: BGR24
 */

#include <stdint.h>
#include <zlib.h>

#include "libavutil/imgutils.h"

#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"

#define BITMAPINFOHEADER_SIZE 0x28
#define TDSF_HEADER_SIZE      0x56
#define TDSB_HEADER_SIZE      0x08

typedef struct TDSCContext {
    AVCodecContext *jpeg_avctx;   // wrapper context for MJPEG

    int width, height;
    GetByteContext gbc;

    AVFrame *refframe;          // full decoded frame (without cursor)
    AVFrame *jpgframe;          // decoded JPEG tile
    uint8_t *tilebuffer;        // buffer containing tile data

    /* zlib interaction */
    uint8_t *deflatebuffer;
    uLongf deflatelen;

    /* All that is cursor */
    uint8_t    *cursor;
    int        cursor_stride;
    int        cursor_w, cursor_h, cursor_x, cursor_y;
    int        cursor_hot_x, cursor_hot_y;
} TDSCContext;

/* 1 byte bits, 1 byte planes, 2 bytes format (probably) */
enum TDSCCursorFormat {
    CUR_FMT_MONO = 0x01010004,
    CUR_FMT_BGRA = 0x20010004,
    CUR_FMT_RGBA = 0x20010008,
};

static av_cold int tdsc_close(AVCodecContext *avctx)
{
    TDSCContext *ctx = avctx->priv_data;

    av_frame_free(&ctx->refframe);
    av_frame_free(&ctx->jpgframe);
    av_freep(&ctx->deflatebuffer);
    av_freep(&ctx->tilebuffer);
    av_freep(&ctx->cursor);
    avcodec_free_context(&ctx->jpeg_avctx);

    return 0;
}

static av_cold int tdsc_init(AVCodecContext *avctx)
{
    TDSCContext *ctx = avctx->priv_data;
    const AVCodec *codec;
    int ret;

    avctx->pix_fmt = AV_PIX_FMT_BGR24;

    /* These needs to be set to estimate buffer and frame size */
    if (!(avctx->width && avctx->height)) {
        av_log(avctx, AV_LOG_ERROR, "Video size not set.\n");
        return AVERROR_INVALIDDATA;
    }

    /* This value should be large enough for a RAW-only frame plus headers */
    ctx->deflatelen = avctx->width * avctx->height * (3 + 1);
    ret = av_reallocp(&ctx->deflatebuffer, ctx->deflatelen);
    if (ret < 0)
        return ret;

    /* Allocate reference and JPEG frame */
    ctx->refframe = av_frame_alloc();
    ctx->jpgframe = av_frame_alloc();
    if (!ctx->refframe || !ctx->jpgframe)
        return AVERROR(ENOMEM);

    /* Prepare everything needed for JPEG decoding */
    codec = avcodec_find_decoder(AV_CODEC_ID_MJPEG);
    if (!codec)
        return AVERROR_BUG;
    ctx->jpeg_avctx = avcodec_alloc_context3(codec);
    if (!ctx->jpeg_avctx)
        return AVERROR(ENOMEM);
    ctx->jpeg_avctx->flags = avctx->flags;
    ctx->jpeg_avctx->flags2 = avctx->flags2;
    ctx->jpeg_avctx->dct_algo = avctx->dct_algo;
    ctx->jpeg_avctx->idct_algo = avctx->idct_algo;
    ret = ff_codec_open2_recursive(ctx->jpeg_avctx, codec, NULL);
    if (ret < 0)
        return ret;

    /* Set the output pixel format on the reference frame */
    ctx->refframe->format = avctx->pix_fmt;

    return 0;
}

#define APPLY_ALPHA(src, new, alpha) \
    src = (src * (256 - alpha) + new * alpha) >> 8

/* Paint a region over a buffer, without drawing out of its bounds. */
static void tdsc_paint_cursor(AVCodecContext *avctx, uint8_t *dst, int stride)
{
    TDSCContext *ctx = avctx->priv_data;
    const uint8_t *cursor = ctx->cursor;
    int x = ctx->cursor_x - ctx->cursor_hot_x;
    int y = ctx->cursor_y - ctx->cursor_hot_y;
    int w = ctx->cursor_w;
    int h = ctx->cursor_h;
    int i, j;

    if (!ctx->cursor)
        return;

    if (x + w > ctx->width)
        w = ctx->width - x;
    if (y + h > ctx->height)
        h = ctx->height - y;
    if (x < 0) {
        w      +=  x;
        cursor += -x * 4;
    } else {
        dst    +=  x * 3;
    }
    if (y < 0) {
        h      +=  y;
        cursor += -y * ctx->cursor_stride;
    } else {
        dst    +=  y * stride;
    }
    if (w < 0 || h < 0)
        return;

    for (j = 0; j < h; j++) {
        for (i = 0; i < w; i++) {
            uint8_t alpha = cursor[i * 4];
            APPLY_ALPHA(dst[i * 3 + 0], cursor[i * 4 + 1], alpha);
            APPLY_ALPHA(dst[i * 3 + 1], cursor[i * 4 + 2], alpha);
            APPLY_ALPHA(dst[i * 3 + 2], cursor[i * 4 + 3], alpha);
        }
        dst    += stride;
        cursor += ctx->cursor_stride;
    }
}

/* Load cursor data and store it in ABGR mode. */
static int tdsc_load_cursor(AVCodecContext *avctx)
{
    TDSCContext *ctx  = avctx->priv_data;
    int i, j, k, ret, cursor_fmt;
    uint8_t *dst;

    ctx->cursor_hot_x = bytestream2_get_le16(&ctx->gbc);
    ctx->cursor_hot_y = bytestream2_get_le16(&ctx->gbc);
    ctx->cursor_w     = bytestream2_get_le16(&ctx->gbc);
    ctx->cursor_h     = bytestream2_get_le16(&ctx->gbc);

    ctx->cursor_stride = FFALIGN(ctx->cursor_w, 32) * 4;
    cursor_fmt = bytestream2_get_le32(&ctx->gbc);

    if (ctx->cursor_x >= avctx->width || ctx->cursor_y >= avctx->height) {
        av_log(avctx, AV_LOG_ERROR,
               "Invalid cursor position (%d.%d outside %dx%d).\n",
               ctx->cursor_x, ctx->cursor_y, avctx->width, avctx->height);
        return AVERROR_INVALIDDATA;
    }
    if (ctx->cursor_w < 1 || ctx->cursor_w > 256 ||
        ctx->cursor_h < 1 || ctx->cursor_h > 256) {
        av_log(avctx, AV_LOG_ERROR,
               "Invalid cursor dimensions %dx%d.\n",
               ctx->cursor_w, ctx->cursor_h);
        return AVERROR_INVALIDDATA;
    }
    if (ctx->cursor_hot_x > ctx->cursor_w ||
        ctx->cursor_hot_y > ctx->cursor_h) {
        av_log(avctx, AV_LOG_WARNING, "Invalid hotspot position %d.%d.\n",
               ctx->cursor_hot_x, ctx->cursor_hot_y);
        ctx->cursor_hot_x = FFMIN(ctx->cursor_hot_x, ctx->cursor_w - 1);
        ctx->cursor_hot_y = FFMIN(ctx->cursor_hot_y, ctx->cursor_h - 1);
    }

    ret = av_reallocp(&ctx->cursor, ctx->cursor_stride * ctx->cursor_h);
    if (ret < 0) {
        av_log(avctx, AV_LOG_ERROR, "Cannot allocate cursor buffer.\n");
        return ret;
    }

    dst = ctx->cursor;
    /* here data is packed in BE */
    switch (cursor_fmt) {
    case CUR_FMT_MONO:
        for (j = 0; j < ctx->cursor_h; j++) {
            for (i = 0; i < ctx->cursor_w; i += 32) {
                uint32_t bits = bytestream2_get_be32(&ctx->gbc);
                for (k = 0; k < 32; k++) {
                    dst[0] = !!(bits & 0x80000000);
                    dst   += 4;
                    bits <<= 1;
                }
            }
            dst += ctx->cursor_stride - ctx->cursor_w * 4;
        }

        dst = ctx->cursor;
        for (j = 0; j < ctx->cursor_h; j++) {
            for (i = 0; i < ctx->cursor_w; i += 32) {
                uint32_t bits = bytestream2_get_be32(&ctx->gbc);
                for (k = 0; k < 32; k++) {
                    int mask_bit = !!(bits & 0x80000000);
                    switch (dst[0] * 2 + mask_bit) {
                    case 0:
                        dst[0] = 0xFF;
                        dst[1] = 0x00;
                        dst[2] = 0x00;
                        dst[3] = 0x00;
                        break;
                    case 1:
                        dst[0] = 0xFF;
                        dst[1] = 0xFF;
                        dst[2] = 0xFF;
                        dst[3] = 0xFF;
                        break;
                    default:
                        dst[0] = 0x00;
                        dst[1] = 0x00;
                        dst[2] = 0x00;
                        dst[3] = 0x00;
                    }
                    dst   += 4;
                    bits <<= 1;
                }
            }
            dst += ctx->cursor_stride - ctx->cursor_w * 4;
        }
        break;
    case CUR_FMT_BGRA:
    case CUR_FMT_RGBA:
        /* Skip monochrome version of the cursor */
        bytestream2_skip(&ctx->gbc,
                         ctx->cursor_h * (FFALIGN(ctx->cursor_w, 32) >> 3));
        if (cursor_fmt & 8) { // RGBA -> ABGR
            for (j = 0; j < ctx->cursor_h; j++) {
                for (i = 0; i < ctx->cursor_w; i++) {
                    int val = bytestream2_get_be32(&ctx->gbc);
                    *dst++ = val >> 24;
                    *dst++ = val >> 16;
                    *dst++ = val >>  8;
                    *dst++ = val >>  0;
                }
                dst += ctx->cursor_stride - ctx->cursor_w * 4;
            }
        } else { // BGRA -> ABGR
            for (j = 0; j < ctx->cursor_h; j++) {
                for (i = 0; i < ctx->cursor_w; i++) {
                    int val = bytestream2_get_be32(&ctx->gbc);
                    *dst++ = val >>  0;
                    *dst++ = val >> 24;
                    *dst++ = val >> 16;
                    *dst++ = val >>  8;
                }
                dst += ctx->cursor_stride - ctx->cursor_w * 4;
            }
        }
        break;
    default:
        avpriv_request_sample(avctx, "Cursor format %08x", cursor_fmt);
        return AVERROR_PATCHWELCOME;
    }

    return 0;
}

/* Convert a single YUV pixel to RGB. */
static inline void tdsc_yuv2rgb(uint8_t *out, int Y, int U, int V)
{
    out[0] = av_clip_uint8(Y + (             91881 * V + 32768 >> 16));
    out[1] = av_clip_uint8(Y + (-22554 * U - 46802 * V + 32768 >> 16));
    out[2] = av_clip_uint8(Y + (116130 * U             + 32768 >> 16));
}

/* Convert a YUV420 buffer to a RGB buffer. */
static av_always_inline void tdsc_blit(uint8_t *dst, int dst_stride,
                                       const uint8_t *srcy, int srcy_stride,
                                       const uint8_t *srcu, const uint8_t *srcv,
                                       int srcuv_stride, int width, int height)
{
    int col, line;
    for (line = 0; line < height; line++) {
        for (col = 0; col < width; col++)
            tdsc_yuv2rgb(dst + col * 3, srcy[col],
                         srcu[col >> 1] - 128, srcv[col >> 1] - 128);

        dst  +=   dst_stride;
        srcy +=  srcy_stride;
        srcu += srcuv_stride * (line & 1);
        srcv += srcuv_stride * (line & 1);
    }
}

/* Invoke the MJPEG decoder to decode the tile. */
static int tdsc_decode_jpeg_tile(AVCodecContext *avctx, int tile_size,
                                 int x, int y, int w, int h)
{
    TDSCContext *ctx = avctx->priv_data;
    AVPacket jpkt;
    int ret;

    /* Prepare a packet and send to the MJPEG decoder */
    av_init_packet(&jpkt);
    jpkt.data = ctx->tilebuffer;
    jpkt.size = tile_size;

    ret = avcodec_send_packet(ctx->jpeg_avctx, &jpkt);
    if (ret < 0) {
        av_log(avctx, AV_LOG_ERROR, "Error submitting a packet for decoding\n");
        return ret;
    }

    ret = avcodec_receive_frame(ctx->jpeg_avctx, ctx->jpgframe);
    if (ret < 0 || ctx->jpgframe->format != AV_PIX_FMT_YUVJ420P) {
        av_log(avctx, AV_LOG_ERROR,
               "JPEG decoding error (%d).\n", ret);

        /* Normally skip, error if explode */
        if (avctx->err_recognition & AV_EF_EXPLODE)
            return AVERROR_INVALIDDATA;
        else
            return 0;
    }

    /* Let's paint onto the buffer */
    tdsc_blit(ctx->refframe->data[0] + x * 3 + ctx->refframe->linesize[0] * y,
              ctx->refframe->linesize[0],
              ctx->jpgframe->data[0], ctx->jpgframe->linesize[0],
              ctx->jpgframe->data[1], ctx->jpgframe->data[2],
              ctx->jpgframe->linesize[1], w, h);

    av_frame_unref(ctx->jpgframe);

    return 0;
}

/* Parse frame and either copy data or decode JPEG. */
static int tdsc_decode_tiles(AVCodecContext *avctx, int number_tiles)
{
    TDSCContext *ctx = avctx->priv_data;
    int i;

    /* Iterate over the number of tiles */
    for (i = 0; i < number_tiles; i++) {
        int tile_size;
        int tile_mode;
        int x, y, x2, y2, w, h;
        int ret;

        if (bytestream2_get_bytes_left(&ctx->gbc) < 4 ||
            bytestream2_get_le32(&ctx->gbc) != MKTAG('T','D','S','B') ||
            bytestream2_get_bytes_left(&ctx->gbc) < TDSB_HEADER_SIZE - 4) {
            av_log(avctx, AV_LOG_ERROR, "TDSB tag is too small.\n");
            return AVERROR_INVALIDDATA;
        }

        tile_size = bytestream2_get_le32(&ctx->gbc);
        if (bytestream2_get_bytes_left(&ctx->gbc) < tile_size)
            return AVERROR_INVALIDDATA;

        tile_mode = bytestream2_get_le32(&ctx->gbc);
        bytestream2_skip(&ctx->gbc, 4); // unknown
        x = bytestream2_get_le32(&ctx->gbc);
        y = bytestream2_get_le32(&ctx->gbc);
        x2 = bytestream2_get_le32(&ctx->gbc);
        y2 = bytestream2_get_le32(&ctx->gbc);

        if (x < 0 || y < 0 || x2 <= x || y2 <= y ||
            x2 > ctx->width || y2 > ctx->height
        ) {
            av_log(avctx, AV_LOG_ERROR,
                   "Invalid tile position (%d.%d %d.%d outside %dx%d).\n",
                   x, y, x2, y2, ctx->width, ctx->height);
            return AVERROR_INVALIDDATA;
        }
        w = x2 - x;
        h = y2 - y;

        ret = av_reallocp(&ctx->tilebuffer, tile_size);
        if (!ctx->tilebuffer)
            return ret;

        bytestream2_get_buffer(&ctx->gbc, ctx->tilebuffer, tile_size);

        if (tile_mode == MKTAG('G','E','P','J')) {
            /* Decode JPEG tile and copy it in the reference frame */
            ret = tdsc_decode_jpeg_tile(avctx, tile_size, x, y, w, h);
            if (ret < 0)
                return ret;
        } else if (tile_mode == MKTAG(' ','W','A','R')) {
            /* Just copy the buffer to output */
            av_image_copy_plane(ctx->refframe->data[0] + x * 3 +
                                ctx->refframe->linesize[0] * y,
                                ctx->refframe->linesize[0], ctx->tilebuffer,
                                w * 3, w * 3, h);
        } else {
            av_log(avctx, AV_LOG_ERROR, "Unknown tile type %08x.\n", tile_mode);
            return AVERROR_INVALIDDATA;
        }
        av_log(avctx, AV_LOG_DEBUG, "Tile %d, %dx%d (%d.%d)\n", i, w, h, x, y);
    }

    return 0;
}

static int tdsc_parse_tdsf(AVCodecContext *avctx, int number_tiles)
{
    TDSCContext *ctx = avctx->priv_data;
    int ret, w, h, init_refframe = !ctx->refframe->data[0];

    /* BITMAPINFOHEADER
     * http://msdn.microsoft.com/en-us/library/windows/desktop/dd183376.aspx */
    if (bytestream2_get_le32(&ctx->gbc) != BITMAPINFOHEADER_SIZE)
        return AVERROR_INVALIDDATA;

    /* Store size, but wait for context reinit before updating avctx */
    w =  bytestream2_get_le32(&ctx->gbc);
    h = -bytestream2_get_le32(&ctx->gbc);

    if (bytestream2_get_le16(&ctx->gbc) != 1 ||  // 1 plane
        bytestream2_get_le16(&ctx->gbc) != 24)   // BGR24
        return AVERROR_INVALIDDATA;

    bytestream2_skip(&ctx->gbc, 24); // unused fields

    /* Update sizes */
    if (avctx->width != w || avctx->height != h) {
        av_log(avctx, AV_LOG_DEBUG, "Size update %dx%d -> %d%d.\n",
               avctx->width, avctx->height, ctx->width, ctx->height);
        ret = ff_set_dimensions(avctx, w, h);
        if (ret < 0)
            return ret;
        init_refframe = 1;
    }
    ctx->refframe->width  = ctx->width  = w;
    ctx->refframe->height = ctx->height = h;

    /* Allocate the reference frame if not already done or on size change */
    if (init_refframe) {
        ret = av_frame_get_buffer(ctx->refframe, 0);
        if (ret < 0)
            return ret;
    }

    /* Decode all tiles in a frame */
    return tdsc_decode_tiles(avctx, number_tiles);
}

static int tdsc_parse_dtsm(AVCodecContext *avctx)
{
    TDSCContext *ctx = avctx->priv_data;
    int ret;
    int action = bytestream2_get_le32(&ctx->gbc);

    bytestream2_skip(&ctx->gbc, 4); // some kind of ID or version maybe?

    if (action == 2 || action == 3) {
        /* Load cursor coordinates */
        ctx->cursor_x = bytestream2_get_le32(&ctx->gbc);
        ctx->cursor_y = bytestream2_get_le32(&ctx->gbc);

        /* Load a full cursor sprite */
        if (action == 3) {
            ret = tdsc_load_cursor(avctx);
            /* Do not consider cursor errors fatal unless in explode mode */
            if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
                return ret;
        }
    } else {
        avpriv_request_sample(avctx, "Cursor action %d", action);
    }

    return 0;
}

static int tdsc_decode_frame(AVCodecContext *avctx, void *data,
                             int *got_frame, AVPacket *avpkt)
{
    TDSCContext *ctx = avctx->priv_data;
    AVFrame *frame = data;
    int ret, tag_header, keyframe = 0;
    uLongf dlen;

    /* Resize deflate buffer on resolution change */
    if (ctx->width != avctx->width || ctx->height != avctx->height) {
        ctx->deflatelen = avctx->width * avctx->height * (3 + 1);
        ret = av_reallocp(&ctx->deflatebuffer, ctx->deflatelen);
        if (ret < 0)
            return ret;
    }
    dlen = ctx->deflatelen;

    /* Frames are deflated, need to inflate them first */
    ret = uncompress(ctx->deflatebuffer, &dlen, avpkt->data, avpkt->size);
    if (ret) {
        av_log(avctx, AV_LOG_ERROR, "Deflate error %d.\n", ret);
        return AVERROR_UNKNOWN;
    }

    bytestream2_init(&ctx->gbc, ctx->deflatebuffer, dlen);

    /* Check for tag and for size info */
    if (bytestream2_get_bytes_left(&ctx->gbc) < 4 + 4) {
        av_log(avctx, AV_LOG_ERROR, "Frame is too small.\n");
        return AVERROR_INVALIDDATA;
    }

    /* Read tag */
    tag_header = bytestream2_get_le32(&ctx->gbc);

    if (tag_header == MKTAG('T','D','S','F')) {
        int number_tiles;
        if (bytestream2_get_bytes_left(&ctx->gbc) < TDSF_HEADER_SIZE) {
            av_log(avctx, AV_LOG_ERROR, "TDSF tag is too small.\n");
            return AVERROR_INVALIDDATA;
        }
        /* First 4 bytes here are the number of GEPJ/WAR tiles in this frame */
        number_tiles = bytestream2_get_le32(&ctx->gbc);

        bytestream2_skip(&ctx->gbc, 4); // internal timestamp maybe?
        keyframe = bytestream2_get_le32(&ctx->gbc) == 0x30;

        ret = tdsc_parse_tdsf(avctx, number_tiles);
        if (ret < 0)
            return ret;

        /* Check if there is anything else we are able to parse */
        if (bytestream2_get_bytes_left(&ctx->gbc) >= 4 + 4)
            tag_header = bytestream2_get_le32(&ctx->gbc);
    }

    /* This tag can be after a TDSF block or on its own frame */
    if (tag_header == MKTAG('D','T','S','M')) {
        /* First 4 bytes here are the total size in bytes for this frame */
        int tag_size = bytestream2_get_le32(&ctx->gbc);

        if (bytestream2_get_bytes_left(&ctx->gbc) < tag_size) {
            av_log(avctx, AV_LOG_ERROR, "DTSM tag is too small.\n");
            return AVERROR_INVALIDDATA;
        }

        ret = tdsc_parse_dtsm(avctx);
        if (ret < 0)
            return ret;
    }

    /* Get the output frame and copy the reference frame */
    ret = ff_get_buffer(avctx, frame, 0);
    if (ret < 0)
        return ret;

    ret = av_frame_copy(frame, ctx->refframe);
    if (ret < 0)
        return ret;

    /* Paint the cursor on the output frame */
    tdsc_paint_cursor(avctx, frame->data[0], frame->linesize[0]);

    /* Frame is ready to be output */
    if (keyframe) {
        frame->pict_type = AV_PICTURE_TYPE_I;
        frame->key_frame = 1;
    } else {
        frame->pict_type = AV_PICTURE_TYPE_P;
    }
    *got_frame = 1;

    return avpkt->size;
}

AVCodec ff_tdsc_decoder = {
    .name           = "tdsc",
    .long_name      = NULL_IF_CONFIG_SMALL("TDSC"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_TDSC,
    .init           = tdsc_init,
    .decode         = tdsc_decode_frame,
    .close          = tdsc_close,
    .priv_data_size = sizeof(TDSCContext),
    .capabilities   = AV_CODEC_CAP_DR1,
    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
                      FF_CODEC_CAP_INIT_CLEANUP,
};


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* TDSC decoder
3			* Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
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			* TDSC decoder
25			*
26			* Fourcc: TSDC
27			*
28			* TDSC is very simple. It codes picture by tiles, storing them in raw BGR24
29			* format or compressing them in JPEG. Frames can be full pictures or just
30			* updates to the previous frame. Cursor is found in its own frame or at the
31			* bottom of the picture. Every frame is then packed with zlib.
32			*
33			* Supports: BGR24
34			*/
35
36			#include <stdint.h>
37			#include <zlib.h>
38
39			#include "libavutil/imgutils.h"
40
41			#include "avcodec.h"
42			#include "bytestream.h"
43			#include "internal.h"
44
45			#define BITMAPINFOHEADER_SIZE 0x28
46			#define TDSF_HEADER_SIZE 0x56
47			#define TDSB_HEADER_SIZE 0x08
48
49			typedef struct TDSCContext {
50			AVCodecContext *jpeg_avctx; // wrapper context for MJPEG
51
52			int width, height;
53			GetByteContext gbc;
54
55			AVFrame *refframe; // full decoded frame (without cursor)
56			AVFrame *jpgframe; // decoded JPEG tile
57			uint8_t *tilebuffer; // buffer containing tile data
58
59			/* zlib interaction */
60			uint8_t *deflatebuffer;
61			uLongf deflatelen;
62
63			/* All that is cursor */
64			uint8_t *cursor;
65			int cursor_stride;
66			int cursor_w, cursor_h, cursor_x, cursor_y;
67			int cursor_hot_x, cursor_hot_y;
68			} TDSCContext;
69
70			/* 1 byte bits, 1 byte planes, 2 bytes format (probably) */
71			enum TDSCCursorFormat {
72			CUR_FMT_MONO = 0x01010004,
73			CUR_FMT_BGRA = 0x20010004,
74			CUR_FMT_RGBA = 0x20010008,
75			};
76
77		2	static av_cold int tdsc_close(AVCodecContext *avctx)
78			{
79		2	TDSCContext *ctx = avctx->priv_data;
80
81		2	av_frame_free(&ctx->refframe);
82		2	av_frame_free(&ctx->jpgframe);
83		2	av_freep(&ctx->deflatebuffer);
84		2	av_freep(&ctx->tilebuffer);
85		2	av_freep(&ctx->cursor);
86		2	avcodec_free_context(&ctx->jpeg_avctx);
87
88		2	return 0;
89			}
90
91		2	static av_cold int tdsc_init(AVCodecContext *avctx)
92			{
93		2	TDSCContext *ctx = avctx->priv_data;
94			const AVCodec *codec;
95			int ret;
96
97		2	avctx->pix_fmt = AV_PIX_FMT_BGR24;
98
99			/* These needs to be set to estimate buffer and frame size */
100	✓✗✗✓	2	if (!(avctx->width && avctx->height)) {
101			av_log(avctx, AV_LOG_ERROR, "Video size not set.\n");
102			return AVERROR_INVALIDDATA;
103			}
104
105			/* This value should be large enough for a RAW-only frame plus headers */
106		2	ctx->deflatelen = avctx->width * avctx->height * (3 + 1);
107		2	ret = av_reallocp(&ctx->deflatebuffer, ctx->deflatelen);
108	✗✓	2	if (ret < 0)
109			return ret;
110
111			/* Allocate reference and JPEG frame */
112		2	ctx->refframe = av_frame_alloc();
113		2	ctx->jpgframe = av_frame_alloc();
114	✓✗✗✓	2	if (!ctx->refframe \|\| !ctx->jpgframe)
115			return AVERROR(ENOMEM);
116
117			/* Prepare everything needed for JPEG decoding */
118		2	codec = avcodec_find_decoder(AV_CODEC_ID_MJPEG);
119	✗✓	2	if (!codec)
120			return AVERROR_BUG;
121		2	ctx->jpeg_avctx = avcodec_alloc_context3(codec);
122	✗✓	2	if (!ctx->jpeg_avctx)
123			return AVERROR(ENOMEM);
124		2	ctx->jpeg_avctx->flags = avctx->flags;
125		2	ctx->jpeg_avctx->flags2 = avctx->flags2;
126		2	ctx->jpeg_avctx->dct_algo = avctx->dct_algo;
127		2	ctx->jpeg_avctx->idct_algo = avctx->idct_algo;
128		2	ret = ff_codec_open2_recursive(ctx->jpeg_avctx, codec, NULL);
129	✗✓	2	if (ret < 0)
130			return ret;
131
132			/* Set the output pixel format on the reference frame */
133		2	ctx->refframe->format = avctx->pix_fmt;
134
135		2	return 0;
136			}
137
138			#define APPLY_ALPHA(src, new, alpha) \
139			src = (src * (256 - alpha) + new * alpha) >> 8
140
141			/* Paint a region over a buffer, without drawing out of its bounds. */
142		41	static void tdsc_paint_cursor(AVCodecContext avctx, uint8_t dst, int stride)
143			{
144		41	TDSCContext *ctx = avctx->priv_data;
145		41	const uint8_t *cursor = ctx->cursor;
146		41	int x = ctx->cursor_x - ctx->cursor_hot_x;
147		41	int y = ctx->cursor_y - ctx->cursor_hot_y;
148		41	int w = ctx->cursor_w;
149		41	int h = ctx->cursor_h;
150			int i, j;
151
152	✓✓	41	if (!ctx->cursor)
153		17	return;
154
155	✗✓	24	if (x + w > ctx->width)
156			w = ctx->width - x;
157	✗✓	24	if (y + h > ctx->height)
158			h = ctx->height - y;
159	✗✓	24	if (x < 0) {
160			w += x;
161			cursor += -x * 4;
162			} else {
163		24	dst += x * 3;
164			}
165	✗✓	24	if (y < 0) {
166			h += y;
167			cursor += -y * ctx->cursor_stride;
168			} else {
169		24	dst += y * stride;
170			}
171	✓✗✗✓	24	if (w < 0 \|\| h < 0)
172			return;
173
174	✓✓	799	for (j = 0; j < h; j++) {
175	✓✓	25926	for (i = 0; i < w; i++) {
176		25151	uint8_t alpha = cursor[i * 4];
177		25151	APPLY_ALPHA(dst[i * 3 + 0], cursor[i * 4 + 1], alpha);
178		25151	APPLY_ALPHA(dst[i * 3 + 1], cursor[i * 4 + 2], alpha);
179		25151	APPLY_ALPHA(dst[i * 3 + 2], cursor[i * 4 + 3], alpha);
180			}
181		775	dst += stride;
182		775	cursor += ctx->cursor_stride;
183			}
184			}
185
186			/* Load cursor data and store it in ABGR mode. */
187		3	static int tdsc_load_cursor(AVCodecContext *avctx)
188			{
189		3	TDSCContext *ctx = avctx->priv_data;
190			int i, j, k, ret, cursor_fmt;
191			uint8_t *dst;
192
193		3	ctx->cursor_hot_x = bytestream2_get_le16(&ctx->gbc);
194		3	ctx->cursor_hot_y = bytestream2_get_le16(&ctx->gbc);
195		3	ctx->cursor_w = bytestream2_get_le16(&ctx->gbc);
196		3	ctx->cursor_h = bytestream2_get_le16(&ctx->gbc);
197
198		3	ctx->cursor_stride = FFALIGN(ctx->cursor_w, 32) * 4;
199		3	cursor_fmt = bytestream2_get_le32(&ctx->gbc);
200
201	✓✗✗✓	3	if (ctx->cursor_x >= avctx->width \|\| ctx->cursor_y >= avctx->height) {
202			av_log(avctx, AV_LOG_ERROR,
203			"Invalid cursor position (%d.%d outside %dx%d).\n",
204			ctx->cursor_x, ctx->cursor_y, avctx->width, avctx->height);
205			return AVERROR_INVALIDDATA;
206			}
207	✓✗✓✗	3	if (ctx->cursor_w < 1 \|\| ctx->cursor_w > 256 \|\|
208	✓✗✗✓	3	ctx->cursor_h < 1 \|\| ctx->cursor_h > 256) {
209			av_log(avctx, AV_LOG_ERROR,
210			"Invalid cursor dimensions %dx%d.\n",
211			ctx->cursor_w, ctx->cursor_h);
212			return AVERROR_INVALIDDATA;
213			}
214	✓✗	3	if (ctx->cursor_hot_x > ctx->cursor_w \|\|
215	✗✓	3	ctx->cursor_hot_y > ctx->cursor_h) {
216			av_log(avctx, AV_LOG_WARNING, "Invalid hotspot position %d.%d.\n",
217			ctx->cursor_hot_x, ctx->cursor_hot_y);
218			ctx->cursor_hot_x = FFMIN(ctx->cursor_hot_x, ctx->cursor_w - 1);
219			ctx->cursor_hot_y = FFMIN(ctx->cursor_hot_y, ctx->cursor_h - 1);
220			}
221
222		3	ret = av_reallocp(&ctx->cursor, ctx->cursor_stride * ctx->cursor_h);
223	✗✓	3	if (ret < 0) {
224			av_log(avctx, AV_LOG_ERROR, "Cannot allocate cursor buffer.\n");
225			return ret;
226			}
227
228		3	dst = ctx->cursor;
229			/* here data is packed in BE */
230	✓✓✗	3	switch (cursor_fmt) {
231		2	case CUR_FMT_MONO:
232	✓✓	66	for (j = 0; j < ctx->cursor_h; j++) {
233	✓✓	128	for (i = 0; i < ctx->cursor_w; i += 32) {
234		64	uint32_t bits = bytestream2_get_be32(&ctx->gbc);
235	✓✓	2112	for (k = 0; k < 32; k++) {
236		2048	dst[0] = !!(bits & 0x80000000);
237		2048	dst += 4;
238		2048	bits <<= 1;
239			}
240			}
241		64	dst += ctx->cursor_stride - ctx->cursor_w * 4;
242			}
243
244		2	dst = ctx->cursor;
245	✓✓	66	for (j = 0; j < ctx->cursor_h; j++) {
246	✓✓	128	for (i = 0; i < ctx->cursor_w; i += 32) {
247		64	uint32_t bits = bytestream2_get_be32(&ctx->gbc);
248	✓✓	2112	for (k = 0; k < 32; k++) {
249		2048	int mask_bit = !!(bits & 0x80000000);
250	✓✓✓	2048	switch (dst[0] * 2 + mask_bit) {
251		104	case 0:
252		104	dst[0] = 0xFF;
253		104	dst[1] = 0x00;
254		104	dst[2] = 0x00;
255		104	dst[3] = 0x00;
256		104	break;
257		178	case 1:
258		178	dst[0] = 0xFF;
259		178	dst[1] = 0xFF;
260		178	dst[2] = 0xFF;
261		178	dst[3] = 0xFF;
262		178	break;
263		1766	default:
264		1766	dst[0] = 0x00;
265		1766	dst[1] = 0x00;
266		1766	dst[2] = 0x00;
267		1766	dst[3] = 0x00;
268			}
269		2048	dst += 4;
270		2048	bits <<= 1;
271			}
272			}
273		64	dst += ctx->cursor_stride - ctx->cursor_w * 4;
274			}
275		2	break;
276		1	case CUR_FMT_BGRA:
277			case CUR_FMT_RGBA:
278			/* Skip monochrome version of the cursor */
279		1	bytestream2_skip(&ctx->gbc,
280		1	ctx->cursor_h * (FFALIGN(ctx->cursor_w, 32) >> 3));
281	✓✗	1	if (cursor_fmt & 8) { // RGBA -> ABGR
282	✓✓	40	for (j = 0; j < ctx->cursor_h; j++) {
283	✓✓	1638	for (i = 0; i < ctx->cursor_w; i++) {
284		1599	int val = bytestream2_get_be32(&ctx->gbc);
285		1599	*dst++ = val >> 24;
286		1599	*dst++ = val >> 16;
287		1599	*dst++ = val >> 8;
288		1599	*dst++ = val >> 0;
289			}
290		39	dst += ctx->cursor_stride - ctx->cursor_w * 4;
291			}
292			} else { // BGRA -> ABGR
293			for (j = 0; j < ctx->cursor_h; j++) {
294			for (i = 0; i < ctx->cursor_w; i++) {
295			int val = bytestream2_get_be32(&ctx->gbc);
296			*dst++ = val >> 0;
297			*dst++ = val >> 24;
298			*dst++ = val >> 16;
299			*dst++ = val >> 8;
300			}
301			dst += ctx->cursor_stride - ctx->cursor_w * 4;
302			}
303			}
304		1	break;
305			default:
306			avpriv_request_sample(avctx, "Cursor format %08x", cursor_fmt);
307			return AVERROR_PATCHWELCOME;
308			}
309
310		3	return 0;
311			}
312
313			/* Convert a single YUV pixel to RGB. */
314		1231360	static inline void tdsc_yuv2rgb(uint8_t *out, int Y, int U, int V)
315			{
316		1231360	out[0] = av_clip_uint8(Y + ( 91881 * V + 32768 >> 16));
317		1231360	out[1] = av_clip_uint8(Y + (-22554 * U - 46802 * V + 32768 >> 16));
318		1231360	out[2] = av_clip_uint8(Y + (116130 * U + 32768 >> 16));
319		1231360	}
320
321			/* Convert a YUV420 buffer to a RGB buffer. */
322		273	static av_always_inline void tdsc_blit(uint8_t *dst, int dst_stride,
323			const uint8_t *srcy, int srcy_stride,
324			const uint8_t srcu, const uint8_t srcv,
325			int srcuv_stride, int width, int height)
326			{
327			int col, line;
328	✓✓	8305	for (line = 0; line < height; line++) {
329	✓✓	1239392	for (col = 0; col < width; col++)
330		1231360	tdsc_yuv2rgb(dst + col * 3, srcy[col],
331		1231360	srcu[col >> 1] - 128, srcv[col >> 1] - 128);
332
333		8032	dst += dst_stride;
334		8032	srcy += srcy_stride;
335		8032	srcu += srcuv_stride * (line & 1);
336		8032	srcv += srcuv_stride * (line & 1);
337			}
338		273	}
339
340			/* Invoke the MJPEG decoder to decode the tile. */
341		273	static int tdsc_decode_jpeg_tile(AVCodecContext *avctx, int tile_size,
342			int x, int y, int w, int h)
343			{
344		273	TDSCContext *ctx = avctx->priv_data;
345			AVPacket jpkt;
346			int ret;
347
348			/* Prepare a packet and send to the MJPEG decoder */
349		273	av_init_packet(&jpkt);
350		273	jpkt.data = ctx->tilebuffer;
351		273	jpkt.size = tile_size;
352
353		273	ret = avcodec_send_packet(ctx->jpeg_avctx, &jpkt);
354	✗✓	273	if (ret < 0) {
355			av_log(avctx, AV_LOG_ERROR, "Error submitting a packet for decoding\n");
356			return ret;
357			}
358
359		273	ret = avcodec_receive_frame(ctx->jpeg_avctx, ctx->jpgframe);
360	✓✗✗✓	273	if (ret < 0 \|\| ctx->jpgframe->format != AV_PIX_FMT_YUVJ420P) {
361			av_log(avctx, AV_LOG_ERROR,
362			"JPEG decoding error (%d).\n", ret);
363
364			/* Normally skip, error if explode */
365			if (avctx->err_recognition & AV_EF_EXPLODE)
366			return AVERROR_INVALIDDATA;
367			else
368			return 0;
369			}
370
371			/* Let's paint onto the buffer */
372		273	tdsc_blit(ctx->refframe->data[0] + x * 3 + ctx->refframe->linesize[0] * y,
373		273	ctx->refframe->linesize[0],
374		273	ctx->jpgframe->data[0], ctx->jpgframe->linesize[0],
375		273	ctx->jpgframe->data[1], ctx->jpgframe->data[2],
376		273	ctx->jpgframe->linesize[1], w, h);
377
378		273	av_frame_unref(ctx->jpgframe);
379
380		273	return 0;
381			}
382
383			/* Parse frame and either copy data or decode JPEG. */
384		36	static int tdsc_decode_tiles(AVCodecContext *avctx, int number_tiles)
385			{
386		36	TDSCContext *ctx = avctx->priv_data;
387			int i;
388
389			/* Iterate over the number of tiles */
390	✓✓	598	for (i = 0; i < number_tiles; i++) {
391			int tile_size;
392			int tile_mode;
393			int x, y, x2, y2, w, h;
394			int ret;
395
396	✓✗✓✗	1124	if (bytestream2_get_bytes_left(&ctx->gbc) < 4 \|\|
397	✗✓	1124	bytestream2_get_le32(&ctx->gbc) != MKTAG('T','D','S','B') \|\|
398		562	bytestream2_get_bytes_left(&ctx->gbc) < TDSB_HEADER_SIZE - 4) {
399			av_log(avctx, AV_LOG_ERROR, "TDSB tag is too small.\n");
400			return AVERROR_INVALIDDATA;
401			}
402
403		562	tile_size = bytestream2_get_le32(&ctx->gbc);
404	✗✓	562	if (bytestream2_get_bytes_left(&ctx->gbc) < tile_size)
405			return AVERROR_INVALIDDATA;
406
407		562	tile_mode = bytestream2_get_le32(&ctx->gbc);
408		562	bytestream2_skip(&ctx->gbc, 4); // unknown
409		562	x = bytestream2_get_le32(&ctx->gbc);
410		562	y = bytestream2_get_le32(&ctx->gbc);
411		562	x2 = bytestream2_get_le32(&ctx->gbc);
412		562	y2 = bytestream2_get_le32(&ctx->gbc);
413
414	✓✗✓✗ ✓✗✓✗	562	if (x < 0 \|\| y < 0 \|\| x2 <= x \|\| y2 <= y \|\|
415	✓✗✗✓	562	x2 > ctx->width \|\| y2 > ctx->height
416			) {
417			av_log(avctx, AV_LOG_ERROR,
418			"Invalid tile position (%d.%d %d.%d outside %dx%d).\n",
419			x, y, x2, y2, ctx->width, ctx->height);
420			return AVERROR_INVALIDDATA;
421			}
422		562	w = x2 - x;
423		562	h = y2 - y;
424
425		562	ret = av_reallocp(&ctx->tilebuffer, tile_size);
426	✗✓	562	if (!ctx->tilebuffer)
427			return ret;
428
429		562	bytestream2_get_buffer(&ctx->gbc, ctx->tilebuffer, tile_size);
430
431	✓✓	562	if (tile_mode == MKTAG('G','E','P','J')) {
432			/* Decode JPEG tile and copy it in the reference frame */
433		273	ret = tdsc_decode_jpeg_tile(avctx, tile_size, x, y, w, h);
434	✗✓	273	if (ret < 0)
435			return ret;
436	✓✗	289	} else if (tile_mode == MKTAG(' ','W','A','R')) {
437			/* Just copy the buffer to output */
438		289	av_image_copy_plane(ctx->refframe->data[0] + x * 3 +
439		289	ctx->refframe->linesize[0] * y,
440		289	ctx->refframe->linesize[0], ctx->tilebuffer,
441			w * 3, w * 3, h);
442			} else {
443			av_log(avctx, AV_LOG_ERROR, "Unknown tile type %08x.\n", tile_mode);
444			return AVERROR_INVALIDDATA;
445			}
446		562	av_log(avctx, AV_LOG_DEBUG, "Tile %d, %dx%d (%d.%d)\n", i, w, h, x, y);
447			}
448
449		36	return 0;
450			}
451
452		36	static int tdsc_parse_tdsf(AVCodecContext *avctx, int number_tiles)
453			{
454		36	TDSCContext *ctx = avctx->priv_data;
455		36	int ret, w, h, init_refframe = !ctx->refframe->data[0];
456
457			/* BITMAPINFOHEADER
458			* http://msdn.microsoft.com/en-us/library/windows/desktop/dd183376.aspx */
459	✗✓	36	if (bytestream2_get_le32(&ctx->gbc) != BITMAPINFOHEADER_SIZE)
460			return AVERROR_INVALIDDATA;
461
462			/* Store size, but wait for context reinit before updating avctx */
463		36	w = bytestream2_get_le32(&ctx->gbc);
464		36	h = -bytestream2_get_le32(&ctx->gbc);
465
466	✓✗✗✓	72	if (bytestream2_get_le16(&ctx->gbc) != 1 \|\| // 1 plane
467		36	bytestream2_get_le16(&ctx->gbc) != 24) // BGR24
468			return AVERROR_INVALIDDATA;
469
470		36	bytestream2_skip(&ctx->gbc, 24); // unused fields
471
472			/* Update sizes */
473	✓✗✗✓	36	if (avctx->width != w \|\| avctx->height != h) {
474			av_log(avctx, AV_LOG_DEBUG, "Size update %dx%d -> %d%d.\n",
475			avctx->width, avctx->height, ctx->width, ctx->height);
476			ret = ff_set_dimensions(avctx, w, h);
477			if (ret < 0)
478			return ret;
479			init_refframe = 1;
480			}
481		36	ctx->refframe->width = ctx->width = w;
482		36	ctx->refframe->height = ctx->height = h;
483
484			/* Allocate the reference frame if not already done or on size change */
485	✓✓	36	if (init_refframe) {
486		1	ret = av_frame_get_buffer(ctx->refframe, 0);
487	✗✓	1	if (ret < 0)
488			return ret;
489			}
490
491			/* Decode all tiles in a frame */
492		36	return tdsc_decode_tiles(avctx, number_tiles);
493			}
494
495		34	static int tdsc_parse_dtsm(AVCodecContext *avctx)
496			{
497		34	TDSCContext *ctx = avctx->priv_data;
498			int ret;
499		34	int action = bytestream2_get_le32(&ctx->gbc);
500
501		34	bytestream2_skip(&ctx->gbc, 4); // some kind of ID or version maybe?
502
503	✓✓✓✗	34	if (action == 2 \|\| action == 3) {
504			/* Load cursor coordinates */
505		34	ctx->cursor_x = bytestream2_get_le32(&ctx->gbc);
506		34	ctx->cursor_y = bytestream2_get_le32(&ctx->gbc);
507
508			/* Load a full cursor sprite */
509	✓✓	34	if (action == 3) {
510		3	ret = tdsc_load_cursor(avctx);
511			/* Do not consider cursor errors fatal unless in explode mode */
512	✗✓✗✗	3	if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
513			return ret;
514			}
515			} else {
516			avpriv_request_sample(avctx, "Cursor action %d", action);
517			}
518
519		34	return 0;
520			}
521
522		42	static int tdsc_decode_frame(AVCodecContext avctx, void data,
523			int got_frame, AVPacket avpkt)
524			{
525		42	TDSCContext *ctx = avctx->priv_data;
526		42	AVFrame *frame = data;
527		42	int ret, tag_header, keyframe = 0;
528			uLongf dlen;
529
530			/* Resize deflate buffer on resolution change */
531	✓✓✗✓	42	if (ctx->width != avctx->width \|\| ctx->height != avctx->height) {
532		1	ctx->deflatelen = avctx->width * avctx->height * (3 + 1);
533		1	ret = av_reallocp(&ctx->deflatebuffer, ctx->deflatelen);
534	✗✓	1	if (ret < 0)
535			return ret;
536			}
537		42	dlen = ctx->deflatelen;
538
539			/* Frames are deflated, need to inflate them first */
540		42	ret = uncompress(ctx->deflatebuffer, &dlen, avpkt->data, avpkt->size);
541	✓✓	42	if (ret) {
542		1	av_log(avctx, AV_LOG_ERROR, "Deflate error %d.\n", ret);
543		1	return AVERROR_UNKNOWN;
544			}
545
546		41	bytestream2_init(&ctx->gbc, ctx->deflatebuffer, dlen);
547
548			/* Check for tag and for size info */
549	✗✓	41	if (bytestream2_get_bytes_left(&ctx->gbc) < 4 + 4) {
550			av_log(avctx, AV_LOG_ERROR, "Frame is too small.\n");
551			return AVERROR_INVALIDDATA;
552			}
553
554			/* Read tag */
555		41	tag_header = bytestream2_get_le32(&ctx->gbc);
556
557	✓✓	41	if (tag_header == MKTAG('T','D','S','F')) {
558			int number_tiles;
559	✗✓	36	if (bytestream2_get_bytes_left(&ctx->gbc) < TDSF_HEADER_SIZE) {
560			av_log(avctx, AV_LOG_ERROR, "TDSF tag is too small.\n");
561			return AVERROR_INVALIDDATA;
562			}
563			/* First 4 bytes here are the number of GEPJ/WAR tiles in this frame */
564		36	number_tiles = bytestream2_get_le32(&ctx->gbc);
565
566		36	bytestream2_skip(&ctx->gbc, 4); // internal timestamp maybe?
567		36	keyframe = bytestream2_get_le32(&ctx->gbc) == 0x30;
568
569		36	ret = tdsc_parse_tdsf(avctx, number_tiles);
570	✗✓	36	if (ret < 0)
571			return ret;
572
573			/* Check if there is anything else we are able to parse */
574	✓✓	36	if (bytestream2_get_bytes_left(&ctx->gbc) >= 4 + 4)
575		31	tag_header = bytestream2_get_le32(&ctx->gbc);
576			}
577
578			/* This tag can be after a TDSF block or on its own frame */
579	✓✓	41	if (tag_header == MKTAG('D','T','S','M')) {
580			/* First 4 bytes here are the total size in bytes for this frame */
581		34	int tag_size = bytestream2_get_le32(&ctx->gbc);
582
583	✗✓	34	if (bytestream2_get_bytes_left(&ctx->gbc) < tag_size) {
584			av_log(avctx, AV_LOG_ERROR, "DTSM tag is too small.\n");
585			return AVERROR_INVALIDDATA;
586			}
587
588		34	ret = tdsc_parse_dtsm(avctx);
589	✗✓	34	if (ret < 0)
590			return ret;
591			}
592
593			/* Get the output frame and copy the reference frame */
594		41	ret = ff_get_buffer(avctx, frame, 0);
595	✗✓	41	if (ret < 0)
596			return ret;
597
598		41	ret = av_frame_copy(frame, ctx->refframe);
599	✗✓	41	if (ret < 0)
600			return ret;
601
602			/* Paint the cursor on the output frame */
603		41	tdsc_paint_cursor(avctx, frame->data[0], frame->linesize[0]);
604
605			/* Frame is ready to be output */
606	✓✓	41	if (keyframe) {
607		2	frame->pict_type = AV_PICTURE_TYPE_I;
608		2	frame->key_frame = 1;
609			} else {
610		39	frame->pict_type = AV_PICTURE_TYPE_P;
611			}
612		41	*got_frame = 1;
613
614		41	return avpkt->size;
615			}
616
617			AVCodec ff_tdsc_decoder = {
618			.name = "tdsc",
619			.long_name = NULL_IF_CONFIG_SMALL("TDSC"),
620			.type = AVMEDIA_TYPE_VIDEO,
621			.id = AV_CODEC_ID_TDSC,
622			.init = tdsc_init,
623			.decode = tdsc_decode_frame,
624			.close = tdsc_close,
625			.priv_data_size = sizeof(TDSCContext),
626			.capabilities = AV_CODEC_CAP_DR1,
627			.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE \|
628			FF_CODEC_CAP_INIT_CLEANUP,
629			};