diff options
Diffstat (limited to 'libavcodec/fmvc.c')
| -rw-r--r-- | libavcodec/fmvc.c | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/libavcodec/fmvc.c b/libavcodec/fmvc.c new file mode 100644 index 0000000000..1f8b0c5c17 --- /dev/null +++ b/libavcodec/fmvc.c @@ -0,0 +1,627 @@ +/* + * FM Screen Capture Codec decoder + * + * Copyright (c) 2017 Paul B Mahol + * + * 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 "avcodec.h" +#include "bytestream.h" +#include "internal.h" + +#define BLOCK_HEIGHT 112u +#define BLOCK_WIDTH 84u + +typedef struct InterBlock { + int w, h; + int size; + int xor; +} InterBlock; + +typedef struct FMVCContext { + GetByteContext gb; + PutByteContext pb; + uint8_t *buffer; + size_t buffer_size; + uint8_t *pbuffer; + size_t pbuffer_size; + int stride; + int bpp; + int yb, xb; + InterBlock *blocks; + int nb_blocks; +} FMVCContext; + +static int decode_type2(GetByteContext *gb, PutByteContext *pb) +{ + unsigned repeat = 0, first = 1, opcode = 0; + int i, len, pos; + + while (bytestream2_get_bytes_left(gb) > 0) { + GetByteContext gbc; + + while (bytestream2_get_bytes_left(gb) > 0) { + if (first) { + first = 0; + if (bytestream2_peek_byte(gb) > 17) { + len = bytestream2_get_byte(gb) - 17; + if (len < 4) { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + continue; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + if (opcode < 0x10) { + bytestream2_skip(gb, 1); + pos = - (opcode >> 2) - 4 * bytestream2_get_byte(gb) - 2049; + + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + len = opcode & 3; + if (!len) { + repeat = 1; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + } + continue; + } + } + repeat = 0; + } + repeat = 1; + } + if (repeat) { + repeat = 0; + opcode = bytestream2_peek_byte(gb); + if (opcode < 0x10) { + bytestream2_skip(gb, 1); + if (!opcode) { + if (!bytestream2_peek_byte(gb)) { + do { + bytestream2_skip(gb, 1); + opcode += 255; + } while (!bytestream2_peek_byte(gb) && bytestream2_get_bytes_left(gb) > 0); + } + opcode += bytestream2_get_byte(gb) + 15; + } + bytestream2_put_le32(pb, bytestream2_get_le32(gb)); + for (i = opcode - 1; i > 0; --i) + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + opcode = bytestream2_peek_byte(gb); + if (opcode < 0x10) { + bytestream2_skip(gb, 1); + pos = - (opcode >> 2) - 4 * bytestream2_get_byte(gb) - 2049; + + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + len = opcode & 3; + if (!len) { + repeat = 1; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + } + continue; + } + } + } + + if (opcode >= 0x40) { + bytestream2_skip(gb, 1); + pos = - ((opcode >> 2) & 7) - 1 - 8 * bytestream2_get_byte(gb); + len = (opcode >> 5) - 1; + + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + do { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + --len; + } while (len); + + len = opcode & 3; + + if (!len) { + repeat = 1; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + } + continue; + } else if (opcode < 0x20) { + break; + } + len = opcode & 0x1F; + bytestream2_skip(gb, 1); + if (!len) { + if (!bytestream2_peek_byte(gb)) { + do { + bytestream2_skip(gb, 1); + len += 255; + } while (!bytestream2_peek_byte(gb) && bytestream2_get_bytes_left(gb) > 0); + } + len += bytestream2_get_byte(gb) + 31; + } + i = bytestream2_get_le16(gb); + pos = - (i >> 2) - 1; + + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + + if (len < 6 || bytestream2_tell_p(pb) - bytestream2_tell(&gbc) < 4) { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + do { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + --len; + } while (len); + } else { + bytestream2_put_le32(pb, bytestream2_get_le32(&gbc)); + for (len = len - 2; len; --len) + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + } + len = i & 3; + if (!len) { + repeat = 1; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + } + } + bytestream2_skip(gb, 1); + if (opcode < 0x10) { + pos = -(opcode >> 2) - 1 - 4 * bytestream2_get_byte(gb); + + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + len = opcode & 3; + if (!len) { + repeat = 1; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + } + continue; + } + len = opcode & 7; + if (!len) { + if (!bytestream2_peek_byte(gb)) { + do { + bytestream2_skip(gb, 1); + len += 255; + } while (!bytestream2_peek_byte(gb) && bytestream2_get_bytes_left(gb) > 0); + } + len += bytestream2_get_byte(gb) + 7; + } + i = bytestream2_get_le16(gb); + pos = bytestream2_tell_p(pb) - 2048 * (opcode & 8); + pos = pos - (i >> 2); + if (pos == bytestream2_tell_p(pb)) + break; + + pos = pos - 0x4000; + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, pos, SEEK_SET); + + if (len < 6 || bytestream2_tell_p(pb) - bytestream2_tell(&gbc) < 4) { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + do { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + --len; + } while (len); + } else { + bytestream2_put_le32(pb, bytestream2_get_le32(&gbc)); + for (len = len - 2; len; --len) + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + } + + len = i & 3; + if (!len) { + repeat = 1; + } else { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --len; + } while (len); + opcode = bytestream2_peek_byte(gb); + } + } + + return 0; +} + +static int decode_type1(GetByteContext *gb, PutByteContext *pb) +{ + unsigned opcode = 0, len; + int high = 0; + int i, pos; + + while (bytestream2_get_bytes_left(gb) > 0) { + GetByteContext gbc; + + while (bytestream2_get_bytes_left(gb) > 0) { + while (bytestream2_get_bytes_left(gb) > 0) { + opcode = bytestream2_get_byte(gb); + high = opcode >= 0x20; + if (high) + break; + if (opcode) + break; + opcode = bytestream2_get_byte(gb); + if (opcode < 0xF8) { + opcode = opcode + 32; + break; + } + i = opcode - 0xF8; + if (i) { + len = 256; + do { + len *= 2; + --i; + } while (i); + } else { + len = 280; + } + do { + bytestream2_put_le32(pb, bytestream2_get_le32(gb)); + bytestream2_put_le32(pb, bytestream2_get_le32(gb)); + len -= 8; + } while (len && bytestream2_get_bytes_left(gb) > 0); + } + + if (!high) { + do { + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + --opcode; + } while (opcode && bytestream2_get_bytes_left(gb) > 0); + + while (bytestream2_get_bytes_left(gb) > 0) { + GetByteContext gbc; + + opcode = bytestream2_get_byte(gb); + if (opcode >= 0x20) + break; + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + + pos = -(opcode | 32 * bytestream2_get_byte(gb)) - 1; + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(gb)); + } + } + high = 0; + if (opcode < 0x40) + break; + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + pos = (-((opcode & 0x1F) | 32 * bytestream2_get_byte(gb)) - 1); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos, SEEK_SET); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + len = (opcode >> 5) - 1; + do { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + --len; + } while (len && bytestream2_get_bytes_left(&gbc) > 0); + } + len = opcode & 0x1F; + if (!len) { + if (!bytestream2_peek_byte(gb)) { + do { + bytestream2_skip(gb, 1); + len += 255; + } while (!bytestream2_peek_byte(gb) && bytestream2_get_bytes_left(gb) > 0); + } + len += bytestream2_get_byte(gb) + 31; + } + pos = -bytestream2_get_byte(gb); + bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start); + bytestream2_seek(&gbc, bytestream2_tell_p(pb) + pos - (bytestream2_get_byte(gb) << 8), SEEK_SET); + if (bytestream2_tell_p(pb) == bytestream2_tell(&gbc)) + break; + if (len < 5 || bytestream2_tell_p(pb) - bytestream2_tell(&gbc) < 4) { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + } else { + bytestream2_put_le32(pb, bytestream2_get_le32(&gbc)); + len--; + } + do { + bytestream2_put_byte(pb, bytestream2_get_byte(&gbc)); + len--; + } while (len && bytestream2_get_bytes_left(&gbc) > 0); + } + + return 0; +} + +static int decode_frame(AVCodecContext *avctx, + void *data, int *got_frame, + AVPacket *avpkt) +{ + FMVCContext *s = avctx->priv_data; + GetByteContext *gb = &s->gb; + PutByteContext *pb = &s->pb; + AVFrame *frame = data; + int ret, y, x; + + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + + bytestream2_init(gb, avpkt->data, avpkt->size); + bytestream2_skip(gb, 2); + + frame->key_frame = !!bytestream2_get_le16(gb); + frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P; + + if (frame->key_frame) { + const uint8_t *src; + int type, size; + uint8_t *dst; + + type = bytestream2_get_le16(gb); + size = bytestream2_get_le16(gb); + if (size > bytestream2_get_bytes_left(gb)) + return AVERROR_INVALIDDATA; + + bytestream2_init_writer(pb, s->buffer, s->buffer_size); + if (type == 1) { + decode_type1(gb, pb); + } else if (type == 2){ + decode_type2(gb, pb); + } else { + avpriv_report_missing_feature(avctx, "compression %d", type); + return AVERROR_PATCHWELCOME; + } + + src = s->buffer; + dst = frame->data[0] + (avctx->height - 1) * frame->linesize[0]; + for (y = 0; y < avctx->height; y++) { + memcpy(dst, src, avctx->width * s->bpp); + dst -= frame->linesize[0]; + src += s->stride * 4; + } + } else { + int block, nb_blocks, type, k, l; + uint8_t *ssrc, *ddst; + const uint32_t *src; + uint32_t *dst; + + for (block = 0; block < s->nb_blocks; block++) + s->blocks[block].xor = 0; + + nb_blocks = bytestream2_get_le16(gb); + if (nb_blocks > s->nb_blocks) + return AVERROR_INVALIDDATA; + + bytestream2_init_writer(pb, s->pbuffer, s->pbuffer_size); + + type = bytestream2_get_le16(gb); + for (block = 0; block < nb_blocks; block++) { + int size, offset, start = 0; + + offset = bytestream2_get_le16(gb); + if (offset > s->nb_blocks) + return AVERROR_INVALIDDATA; + + size = bytestream2_get_le16(gb); + if (size > bytestream2_get_bytes_left(gb)) + return AVERROR_INVALIDDATA; + + start = bytestream2_tell_p(pb); + if (type == 1) { + decode_type1(gb, pb); + } else if (type == 2){ + decode_type2(gb, pb); + } else { + avpriv_report_missing_feature(avctx, "compression %d", type); + return AVERROR_PATCHWELCOME; + } + + if (s->blocks[offset].size * 4 != bytestream2_tell_p(pb) - start) + return AVERROR_INVALIDDATA; + + s->blocks[offset].xor = 1; + } + + src = (const uint32_t *)s->pbuffer; + dst = (uint32_t *)s->buffer; + + for (block = 0, y = 0; y < s->yb; y++) { + int block_h = s->blocks[block].h; + uint32_t *rect = dst; + + for (x = 0; x < s->xb; x++) { + int block_w = s->blocks[block].w; + uint32_t *row = dst; + + block_h = s->blocks[block].h; + if (s->blocks[block].xor) { + for (k = 0; k < block_h; k++) { + uint32_t *column = dst; + for (l = 0; l < block_w; l++) { + *dst++ ^= *src++; + } + dst = &column[s->stride]; + } + } + dst = &row[block_w]; + ++block; + } + dst = &rect[block_h * s->stride]; + } + + ssrc = s->buffer; + ddst = frame->data[0] + (avctx->height - 1) * frame->linesize[0]; + for (y = 0; y < avctx->height; y++) { + memcpy(ddst, ssrc, avctx->width * s->bpp); + ddst -= frame->linesize[0]; + ssrc += s->stride * 4; + } + } + + *got_frame = 1; + + return avpkt->size; +} + +static av_cold int decode_init(AVCodecContext *avctx) +{ + FMVCContext *s = avctx->priv_data; + int i, j, m, block = 0, h = BLOCK_HEIGHT, w = BLOCK_WIDTH; + + switch (avctx->bits_per_coded_sample) { + case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break; + case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break; + case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break; + default: + av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample); + return AVERROR_INVALIDDATA; + } + + s->stride = (avctx->width * avctx->bits_per_coded_sample + 31) / 32; + s->xb = s->stride / BLOCK_WIDTH; + m = s->stride % BLOCK_WIDTH; + if (m) { + if (m < 37) { + w = m + BLOCK_WIDTH; + } else { + w = m; + s->xb++; + } + } + + s->yb = avctx->height / BLOCK_HEIGHT; + m = avctx->height % BLOCK_HEIGHT; + if (m) { + if (m < 49) { + h = m + BLOCK_HEIGHT; + } else { + h = m; + s->yb++; + } + } + + s->nb_blocks = s->xb * s->yb; + s->blocks = av_calloc(s->nb_blocks, sizeof(*s->blocks)); + if (!s->blocks) + return AVERROR(ENOMEM); + + for (i = 0; i < s->yb; i++) { + for (j = 0; j < s->xb; j++) { + if (i != (s->yb - 1) || j != (s->xb - 1)) { + if (i == s->yb - 1) { + s->blocks[block].w = BLOCK_WIDTH; + s->blocks[block].h = h; + s->blocks[block].size = BLOCK_WIDTH * h; + } else if (j == s->xb - 1) { + s->blocks[block].w = w; + s->blocks[block].h = BLOCK_HEIGHT; + s->blocks[block].size = BLOCK_HEIGHT * w; + } else { + s->blocks[block].w = BLOCK_WIDTH; + s->blocks[block].h = BLOCK_HEIGHT; + s->blocks[block].size = BLOCK_WIDTH * BLOCK_HEIGHT; + } + } else { + s->blocks[block].w = w; + s->blocks[block].h = h; + s->blocks[block].size = w * h; + } + block++; + } + } + + s->bpp = avctx->bits_per_coded_sample >> 3; + s->buffer_size = avctx->width * avctx->height * 4; + s->pbuffer_size = avctx->width * avctx->height * 4; + s->buffer = av_malloc(s->buffer_size); + s->pbuffer = av_malloc(s->pbuffer_size); + if (!s->buffer || !s->pbuffer) + return AVERROR(ENOMEM); + + return 0; +} + +static av_cold int decode_close(AVCodecContext *avctx) +{ + FMVCContext *s = avctx->priv_data; + + av_freep(&s->buffer); + av_freep(&s->pbuffer); + av_freep(&s->blocks); + + return 0; +} + +AVCodec ff_fmvc_decoder = { + .name = "fmvc", + .long_name = NULL_IF_CONFIG_SMALL("FM Screen Capture Codec"), + .type = AVMEDIA_TYPE_VIDEO, + .id = AV_CODEC_ID_FMVC, + .priv_data_size = sizeof(FMVCContext), + .init = decode_init, + .close = decode_close, + .decode = decode_frame, + .capabilities = AV_CODEC_CAP_DR1, + .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | + FF_CODEC_CAP_INIT_CLEANUP, +}; 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