/* * Duck TrueMotion 2.0 Real Time decoder * * 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 <stdio.h> #include <stdlib.h> #include <string.h> #include "libavutil/imgutils.h" #include "libavutil/internal.h" #include "libavutil/intreadwrite.h" #include "libavutil/mem.h" #define BITSTREAM_READER_LE #include "avcodec.h" #include "get_bits.h" #include "internal.h" typedef struct TrueMotion2RTContext { GetBitContext gb; int delta_size; int hscale; } TrueMotion2RTContext; static const int16_t delta_tab2[] = { 5, -7, 36, -36, }; static const int16_t delta_tab3[] = { 2, -3, 8, -8, 18, -18, 36, -36, }; static const int16_t delta_tab4[] = { 1, -1, 2, -3, 8, -8, 18, -18, 36, -36, 54, -54, 96, -96, 144, -144, }; static const int16_t *const delta_tabs[] = { delta_tab2, delta_tab3, delta_tab4, }; /* Returns the number of bytes consumed from the bytestream, or * AVERROR_INVALIDDATA if there was an error while decoding the header. */ static int truemotion2rt_decode_header(AVCodecContext *avctx, const AVPacket *avpkt) { TrueMotion2RTContext *s = avctx->priv_data; int header_size; uint8_t header_buffer[128] = { 0 }; /* logical maximum header size */ const uint8_t *buf = avpkt->data; int size = avpkt->size; int width, height; int ret, i; if (size < 1) { av_log(avctx, AV_LOG_ERROR, "input packet too small (%d)\n", size); return AVERROR_INVALIDDATA; } header_size = ((buf[0] >> 5) | (buf[0] << 3)) & 0x7f; if (header_size < 10) { av_log(avctx, AV_LOG_ERROR, "invalid header size (%d)\n", header_size); return AVERROR_INVALIDDATA; } if (header_size + 1 > size) { av_log(avctx, AV_LOG_ERROR, "input packet too small (%d)\n", size); return AVERROR_INVALIDDATA; } /* unscramble the header bytes with a XOR operation */ for (i = 1; i < header_size; i++) header_buffer[i - 1] = buf[i] ^ buf[i + 1]; s->delta_size = header_buffer[1]; s->hscale = 1 + !!header_buffer[3]; if (s->delta_size < 2 || s->delta_size > 4) return AVERROR_INVALIDDATA; height = AV_RL16(header_buffer + 5); width = AV_RL16(header_buffer + 7); ret = ff_set_dimensions(avctx, width, height); if (ret < 0) return ret; av_log(avctx, AV_LOG_DEBUG, "Header size: %d\n", header_size); return header_size; } static int truemotion2rt_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { TrueMotion2RTContext *s = avctx->priv_data; AVFrame * const p = data; GetBitContext *gb = &s->gb; uint8_t *dst; int x, y, delta_mode; int ret; ret = truemotion2rt_decode_header(avctx, avpkt); if (ret < 0) return ret; if ((avctx->width + s->hscale - 1)/ s->hscale * avctx->height * s->delta_size > avpkt->size * 8LL * 4) return AVERROR_INVALIDDATA; ret = init_get_bits8(gb, avpkt->data + ret, avpkt->size - ret); if (ret < 0) return ret; ret = ff_get_buffer(avctx, p, 0); if (ret < 0) return ret; skip_bits(gb, 32); delta_mode = s->delta_size - 2; dst = p->data[0]; for (y = 0; y < avctx->height; y++) { int diff = 0; for (x = 0; x < avctx->width; x += s->hscale) { diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)]; dst[x] = av_clip_uint8((y ? dst[x - p->linesize[0]] : 0) + diff); } dst += p->linesize[0]; } if (s->hscale > 1) { dst = p->data[0]; for (y = 0; y < avctx->height; y++) { for (x = 1; x < avctx->width; x += s->hscale) dst[x] = dst[x - 1]; dst += p->linesize[0]; } } dst = p->data[0]; for (y = 0; y < avctx->height; y++) { for (x = 0; x < avctx->width; x++) dst[x] = av_clip_uint8(dst[x] + (dst[x] - 128) / 3); dst += p->linesize[0]; } dst = p->data[1]; for (y = 0; y < avctx->height >> 2; y++) { int diff = 0; for (x = 0; x < avctx->width >> 2; x += s->hscale) { diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)]; dst[x] = av_clip_uint8((y ? dst[x - p->linesize[1]] : 128) + diff); } dst += p->linesize[1]; } if (s->hscale > 1) { dst = p->data[1]; for (y = 0; y < avctx->height >> 2; y++) { for (x = 1; x < avctx->width >> 2; x += s->hscale) dst[x] = dst[x - 1]; dst += p->linesize[1]; } } dst = p->data[1]; for (y = 0; y < avctx->height >> 2; y++) { for (x = 0; x < avctx->width >> 2; x++) dst[x] += (dst[x] - 128) / 8; dst += p->linesize[1]; } dst = p->data[2]; for (y = 0; y < avctx->height >> 2; y++) { int diff = 0; for (x = 0; x < avctx->width >> 2; x += s->hscale) { diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)]; dst[x] = av_clip_uint8((y ? dst[x - p->linesize[2]] : 128) + diff); } dst += p->linesize[2]; } if (s->hscale > 1) { dst = p->data[2]; for (y = 0; y < avctx->height >> 2; y++) { for (x = 1; x < avctx->width >> 2; x += s->hscale) dst[x] = dst[x - 1]; dst += p->linesize[2]; } } dst = p->data[2]; for (y = 0; y < avctx->height >> 2; y++) { for (x = 0; x < avctx->width >> 2; x++) dst[x] += (dst[x] - 128) / 8; dst += p->linesize[2]; } p->pict_type = AV_PICTURE_TYPE_I; p->key_frame = 1; *got_frame = 1; return avpkt->size; } static av_cold int truemotion2rt_decode_init(AVCodecContext *avctx) { avctx->pix_fmt = AV_PIX_FMT_YUV410P; return 0; } AVCodec ff_truemotion2rt_decoder = { .name = "truemotion2rt", .long_name = NULL_IF_CONFIG_SMALL("Duck TrueMotion 2.0 Real Time"), .type = AVMEDIA_TYPE_VIDEO, .id = AV_CODEC_ID_TRUEMOTION2RT, .priv_data_size = sizeof(TrueMotion2RTContext), .init = truemotion2rt_decode_init, .decode = truemotion2rt_decode_frame, .capabilities = AV_CODEC_CAP_DR1, .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, };