/* * Chronomaster DFA Video Decoder * Copyright (c) 2011 Konstantin Shishkov * based on work by Vladimir "VAG" Gneushev * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avcodec.h"#include "bytestream.h"#include "libavutil/lzo.h" // for av_memcpy_backptr typedef struct DfaContext {    AVFrame pic;     uint32_t pal[256];    uint8_t *frame_buf;} DfaContext; static av_cold int dfa_decode_init(AVCodecContext *avctx){    DfaContext *s = avctx->priv_data;     avctx->pix_fmt = PIX_FMT_PAL8;     s->frame_buf = av_mallocz(avctx->width * avctx->height + AV_LZO_OUTPUT_PADDING);    if (!s->frame_buf)        return AVERROR(ENOMEM);     return 0;} static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height){    const int size = width * height;     if (bytestream2_get_buffer(gb, frame, size) != size)        return AVERROR_INVALIDDATA;    return 0;} static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height){    const uint8_t *frame_start = frame;    const uint8_t *frame_end   = frame + width * height;    int mask = 0x10000, bitbuf = 0;    int v, count, segments;    unsigned offset;     segments = bytestream2_get_le32(gb);    offset   = bytestream2_get_le32(gb);    if (frame_end - frame <= offset)        return AVERROR_INVALIDDATA;    frame += offset;    while (segments--) {        if (bytestream2_get_bytes_left(gb) < 2)            return AVERROR_INVALIDDATA;        if (mask == 0x10000) {            bitbuf = bytestream2_get_le16u(gb);            mask = 1;        }        if (frame_end - frame < 2)            return AVERROR_INVALIDDATA;        if (bitbuf & mask) {            v = bytestream2_get_le16(gb);            offset = (v & 0x1FFF) << 1;            count = ((v >> 13) + 2) << 1;            if (frame - frame_start < offset || frame_end - frame < count)                return AVERROR_INVALIDDATA;            av_memcpy_backptr(frame, offset, count);            frame += count;        } else {            *frame++ = bytestream2_get_byte(gb);            *frame++ = bytestream2_get_byte(gb);        }        mask <<= 1;    }     return 0;} static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height){    const uint8_t *frame_start = frame;    const uint8_t *frame_end   = frame + width * height;    int mask = 0x10000, bitbuf = 0;    int v, offset, count, segments;     segments = bytestream2_get_le16(gb);    while (segments--) {        if (bytestream2_get_bytes_left(gb) < 2)            return AVERROR_INVALIDDATA;        if (mask == 0x10000) {            bitbuf = bytestream2_get_le16u(gb);            mask = 1;        }        if (frame_end - frame < 2)            return AVERROR_INVALIDDATA;        if (bitbuf & mask) {            v = bytestream2_get_le16(gb);            offset = (v & 0x1FFF) << 1;            count = ((v >> 13) + 2) << 1;            if (frame - frame_start < offset || frame_end - frame < count)                return AVERROR_INVALIDDATA;            // can't use av_memcpy_backptr() since it can overwrite following pixels            for (v = 0; v < count; v++)                frame[v] = frame[v - offset];            frame += count;        } else if (bitbuf & (mask << 1)) {            frame += bytestream2_get_le16(gb);        } else {            *frame++ = bytestream2_get_byte(gb);            *frame++ = bytestream2_get_byte(gb);        }        mask <<= 2;    }     return 0;} static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height){    const uint8_t *frame_start = frame;    const uint8_t *frame_end   = frame + width * height;    int mask = 0x10000, bitbuf = 0;    int i, v, offset, count, segments;     segments = bytestream2_get_le16(gb);    while (segments--) {        if (bytestream2_get_bytes_left(gb) < 2)            return AVERROR_INVALIDDATA;        if (mask == 0x10000) {            bitbuf = bytestream2_get_le16u(gb);            mask = 1;        }        if (frame_end - frame < 2)            return AVERROR_INVALIDDATA;        if (bitbuf & mask) {            v = bytestream2_get_le16(gb);            offset = (v & 0x1FFF) << 2;            count = ((v >> 13) + 2) << 1;            if (frame - frame_start < offset || frame_end - frame < count*2 + width)                return AVERROR_INVALIDDATA;            for (i = 0; i < count; i++) {                frame[0] = frame[1] =                frame[width] = frame[width + 1] = frame[-offset];                 frame += 2;            }        } else if (bitbuf & (mask << 1)) {            frame += bytestream2_get_le16(gb) * 2;        } else {            if (frame_end - frame < width + 2)                return AVERROR_INVALIDDATA;            frame[0] = frame[1] =            frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);            frame += 2;            frame[0] = frame[1] =            frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);            frame += 2;        }        mask <<= 2;    }     return 0;} static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height){    uint8_t *line_ptr;    int count, lines, segments;     count = bytestream2_get_le16(gb);    if (count >= height)        return AVERROR_INVALIDDATA;    frame += width * count;    lines = bytestream2_get_le16(gb);    if (count + lines > height)        return AVERROR_INVALIDDATA;     while (lines--) {        if (bytestream2_get_bytes_left(gb) < 1)            return AVERROR_INVALIDDATA;        line_ptr = frame;        frame += width;        segments = bytestream2_get_byteu(gb);        while (segments--) {            if (frame - line_ptr <= bytestream2_peek_byte(gb))                return AVERROR_INVALIDDATA;            line_ptr += bytestream2_get_byte(gb);            count = (int8_t)bytestream2_get_byte(gb);            if (count >= 0) {                if (frame - line_ptr < count)                    return AVERROR_INVALIDDATA;                if (bytestream2_get_buffer(gb, line_ptr, count) != count)                    return AVERROR_INVALIDDATA;            } else {                count = -count;                if (frame - line_ptr < count)                    return AVERROR_INVALIDDATA;                memset(line_ptr, bytestream2_get_byte(gb), count);            }            line_ptr += count;        }    }     return 0;} static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height){    const uint8_t *frame_end   = frame + width * height;    uint8_t *line_ptr;    int count, i, v, lines, segments;    int y = 0;     lines = bytestream2_get_le16(gb);    if (lines > height)        return AVERROR_INVALIDDATA;     while (lines--) {        if (bytestream2_get_bytes_left(gb) < 2)            return AVERROR_INVALIDDATA;        segments = bytestream2_get_le16u(gb);        while ((segments & 0xC000) == 0xC000) {            unsigned skip_lines = -(int16_t)segments;            unsigned delta = -((int16_t)segments * width);            if (frame_end - frame <= delta || y + lines + skip_lines > height)                return AVERROR_INVALIDDATA;            frame    += delta;            y        += skip_lines;            segments = bytestream2_get_le16(gb);        }        if (segments & 0x8000) {            frame[width - 1] = segments & 0xFF;            segments = bytestream2_get_le16(gb);        }        line_ptr = frame;        frame += width;        y++;        while (segments--) {            if (frame - line_ptr <= bytestream2_peek_byte(gb))                return AVERROR_INVALIDDATA;            line_ptr += bytestream2_get_byte(gb);            count = (int8_t)bytestream2_get_byte(gb);            if (count >= 0) {                if (frame - line_ptr < count * 2)                    return AVERROR_INVALIDDATA;                if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)                    return AVERROR_INVALIDDATA;                line_ptr += count * 2;            } else {                count = -count;                if (frame - line_ptr < count * 2)                    return AVERROR_INVALIDDATA;                v = bytestream2_get_le16(gb);                for (i = 0; i < count; i++)                    bytestream_put_le16(&line_ptr, v);            }        }    }     return 0;} static int decode_unk6(GetByteContext *gb, uint8_t *frame, int width, int height){    return AVERROR_PATCHWELCOME;} static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height){    memset(frame, 0, width * height);    return 0;}  typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height); static const chunk_decoder decoder[8] = {    decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,    decode_unk6, decode_dsw1, decode_blck, decode_dds1,}; static const char* chunk_name[8] = {    "COPY", "TSW1", "BDLT", "WDLT", "????", "DSW1", "BLCK", "DDS1"}; static int dfa_decode_frame(AVCodecContext *avctx,                            void *data, int *data_size,                            AVPacket *avpkt){    DfaContext *s = avctx->priv_data;    GetByteContext gb;    const uint8_t *buf = avpkt->data;    uint32_t chunk_type, chunk_size;    uint8_t *dst;    int ret;    int i, pal_elems;     if (s->pic.data[0])        avctx->release_buffer(avctx, &s->pic);     if ((ret = avctx->get_buffer(avctx, &s->pic))) {        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");        return ret;    }     bytestream2_init(&gb, avpkt->data, avpkt->size);    while (bytestream2_get_bytes_left(&gb) > 0) {        bytestream2_skip(&gb, 4);        chunk_size = bytestream2_get_le32(&gb);        chunk_type = bytestream2_get_le32(&gb);        if (!chunk_type)            break;        if (chunk_type == 1) {            pal_elems = FFMIN(chunk_size / 3, 256);            for (i = 0; i < pal_elems; i++) {                s->pal[i] = bytestream2_get_be24(&gb) << 2;                s->pal[i] |= (s->pal[i] >> 6) & 0x333;            }            s->pic.palette_has_changed = 1;        } else if (chunk_type <= 9) {            if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {                av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",                       chunk_name[chunk_type - 2]);                return AVERROR_INVALIDDATA;            }        } else {            av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %d\n",                   chunk_type);        }        buf += chunk_size;    }     buf = s->frame_buf;    dst = s->pic.data[0];    for (i = 0; i < avctx->height; i++) {        memcpy(dst, buf, avctx->width);        dst += s->pic.linesize[0];        buf += avctx->width;    }    memcpy(s->pic.data[1], s->pal, sizeof(s->pal));     *data_size = sizeof(AVFrame);    *(AVFrame*)data = s->pic;     return avpkt->size;} static av_cold int dfa_decode_end(AVCodecContext *avctx){    DfaContext *s = avctx->priv_data;     if (s->pic.data[0])        avctx->release_buffer(avctx, &s->pic);     av_freep(&s->frame_buf);     return 0;} AVCodec ff_dfa_decoder = {    .name           = "dfa",    .type           = AVMEDIA_TYPE_VIDEO,    .id             = CODEC_ID_DFA,    .priv_data_size = sizeof(DfaContext),    .init           = dfa_decode_init,    .close          = dfa_decode_end,    .decode         = dfa_decode_frame,    .capabilities   = CODEC_CAP_DR1,    .long_name      = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),};