/* * Go2Webinar / Go2Meeting decoder * Copyright (c) 2012 Konstantin Shishkov * Copyright (c) 2013 Maxim Poliakovski * * 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 */ /** * @file * Go2Webinar / Go2Meeting decoder */ #include #include #include "libavutil/intreadwrite.h" #include "avcodec.h" #include "blockdsp.h" #include "bytestream.h" #include "elsdec.h" #include "get_bits.h" #include "idctdsp.h" #include "internal.h" #include "jpegtables.h" #include "mjpeg.h" #define EPIC_PIX_STACK_SIZE 1024 #define EPIC_PIX_STACK_MAX (EPIC_PIX_STACK_SIZE - 1) enum ChunkType { DISPLAY_INFO = 0xC8, TILE_DATA, CURSOR_POS, CURSOR_SHAPE, CHUNK_CC, CHUNK_CD }; enum Compression { COMPR_EPIC_J_B = 2, COMPR_KEMPF_J_B, }; static const uint8_t luma_quant[64] = { 8, 6, 5, 8, 12, 20, 26, 31, 6, 6, 7, 10, 13, 29, 30, 28, 7, 7, 8, 12, 20, 29, 35, 28, 7, 9, 11, 15, 26, 44, 40, 31, 9, 11, 19, 28, 34, 55, 52, 39, 12, 18, 28, 32, 41, 52, 57, 46, 25, 32, 39, 44, 52, 61, 60, 51, 36, 46, 48, 49, 56, 50, 52, 50 }; static const uint8_t chroma_quant[64] = { 9, 9, 12, 24, 50, 50, 50, 50, 9, 11, 13, 33, 50, 50, 50, 50, 12, 13, 28, 50, 50, 50, 50, 50, 24, 33, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, 50, }; typedef struct ePICPixListElem { struct ePICPixListElem *next; uint32_t pixel; uint8_t rung; } ePICPixListElem; typedef struct ePICPixHashElem { uint32_t pix_id; struct ePICPixListElem *list; } ePICPixHashElem; #define EPIC_HASH_SIZE 256 typedef struct ePICPixHash { ePICPixHashElem *bucket[EPIC_HASH_SIZE]; int bucket_size[EPIC_HASH_SIZE]; int bucket_fill[EPIC_HASH_SIZE]; } ePICPixHash; typedef struct ePICContext { ElsDecCtx els_ctx; int next_run_pos; ElsUnsignedRung unsigned_rung; uint8_t W_flag_rung; uint8_t N_flag_rung; uint8_t W_ctx_rung[256]; uint8_t N_ctx_rung[512]; uint8_t nw_pred_rung[256]; uint8_t ne_pred_rung[256]; uint8_t prev_row_rung[14]; uint8_t runlen_zeroes[14]; uint8_t runlen_one; int stack_pos; uint32_t stack[EPIC_PIX_STACK_SIZE]; ePICPixHash hash; } ePICContext; typedef struct JPGContext { BlockDSPContext bdsp; IDCTDSPContext idsp; ScanTable scantable; VLC dc_vlc[2], ac_vlc[2]; int prev_dc[3]; DECLARE_ALIGNED(16, int16_t, block)[6][64]; uint8_t *buf; } JPGContext; typedef struct G2MContext { ePICContext ec; JPGContext jc; int version; int compression; int width, height, bpp; int orig_width, orig_height; int tile_width, tile_height; int tiles_x, tiles_y, tile_x, tile_y; int got_header; uint8_t *framebuf; int framebuf_stride, old_width, old_height; uint8_t *synth_tile, *jpeg_tile, *epic_buf, *epic_buf_base; int tile_stride, epic_buf_stride, old_tile_w, old_tile_h; int swapuv; uint8_t *kempf_buf, *kempf_flags; uint8_t *cursor; int cursor_stride; int cursor_fmt; int cursor_w, cursor_h, cursor_x, cursor_y; int cursor_hot_x, cursor_hot_y; } G2MContext; static av_cold int build_vlc(VLC *vlc, const uint8_t *bits_table, const uint8_t *val_table, int nb_codes, int is_ac) { uint8_t huff_size[256] = { 0 }; uint16_t huff_code[256]; uint16_t huff_sym[256]; int i; ff_mjpeg_build_huffman_codes(huff_size, huff_code, bits_table, val_table); for (i = 0; i < 256; i++) huff_sym[i] = i + 16 * is_ac; if (is_ac) huff_sym[0] = 16 * 256; return ff_init_vlc_sparse(vlc, 9, nb_codes, huff_size, 1, 1, huff_code, 2, 2, huff_sym, 2, 2, 0); } static av_cold int jpg_init(AVCodecContext *avctx, JPGContext *c) { int ret; ret = build_vlc(&c->dc_vlc[0], avpriv_mjpeg_bits_dc_luminance, avpriv_mjpeg_val_dc, 12, 0); if (ret) return ret; ret = build_vlc(&c->dc_vlc[1], avpriv_mjpeg_bits_dc_chrominance, avpriv_mjpeg_val_dc, 12, 0); if (ret) return ret; ret = build_vlc(&c->ac_vlc[0], avpriv_mjpeg_bits_ac_luminance, avpriv_mjpeg_val_ac_luminance, 251, 1); if (ret) return ret; ret = build_vlc(&c->ac_vlc[1], avpriv_mjpeg_bits_ac_chrominance, avpriv_mjpeg_val_ac_chrominance, 251, 1); if (ret) return ret; ff_blockdsp_init(&c->bdsp, avctx); ff_idctdsp_init(&c->idsp, avctx); ff_init_scantable(c->idsp.idct_permutation, &c->scantable, ff_zigzag_direct); return 0; } static av_cold void jpg_free_context(JPGContext *ctx) { int i; for (i = 0; i < 2; i++) { ff_free_vlc(&ctx->dc_vlc[i]); ff_free_vlc(&ctx->ac_vlc[i]); } av_freep(&ctx->buf); } static void jpg_unescape(const uint8_t *src, int src_size, uint8_t *dst, int *dst_size) { const uint8_t *src_end = src + src_size; uint8_t *dst_start = dst; while (src < src_end) { uint8_t x = *src++; *dst++ = x; if (x == 0xFF && !*src) src++; } *dst_size = dst - dst_start; } static int jpg_decode_block(JPGContext *c, GetBitContext *gb, int plane, int16_t *block) { int dc, val, pos; const int is_chroma = !!plane; const uint8_t *qmat = is_chroma ? chroma_quant : luma_quant; c->bdsp.clear_block(block); dc = get_vlc2(gb, c->dc_vlc[is_chroma].table, 9, 3); if (dc < 0) return AVERROR_INVALIDDATA; if (dc) dc = get_xbits(gb, dc); dc = dc * qmat[0] + c->prev_dc[plane]; block[0] = dc; c->prev_dc[plane] = dc; pos = 0; while (pos < 63) { val = get_vlc2(gb, c->ac_vlc[is_chroma].table, 9, 3); if (val < 0) return AVERROR_INVALIDDATA; pos += val >> 4; val &= 0xF; if (pos > 63) return val ? AVERROR_INVALIDDATA : 0; if (val) { int nbits = val; val = get_xbits(gb, nbits); val *= qmat[ff_zigzag_direct[pos]]; block[c->scantable.permutated[pos]] = val; } } return 0; } static inline void yuv2rgb(uint8_t *out, int ridx, int Y, int U, int V) { out[ridx] = av_clip_uint8(Y + (91881 * V + 32768 >> 16)); out[1] = av_clip_uint8(Y + (-22554 * U - 46802 * V + 32768 >> 16)); out[2 - ridx] = av_clip_uint8(Y + (116130 * U + 32768 >> 16)); } static int jpg_decode_data(JPGContext *c, int width, int height, const uint8_t *src, int src_size, uint8_t *dst, int dst_stride, const uint8_t *mask, int mask_stride, int num_mbs, int swapuv) { GetBitContext gb; int mb_w, mb_h, mb_x, mb_y, i, j; int bx, by; int unesc_size; int ret; const int ridx = swapuv ? 2 : 0; if ((ret = av_reallocp(&c->buf, src_size + AV_INPUT_BUFFER_PADDING_SIZE)) < 0) return ret; jpg_unescape(src, src_size, c->buf, &unesc_size); memset(c->buf + unesc_size, 0, AV_INPUT_BUFFER_PADDING_SIZE); init_get_bits(&gb, c->buf, unesc_size * 8); width = FFALIGN(width, 16); mb_w = width >> 4; mb_h = (height + 15) >> 4; if (!num_mbs) num_mbs = mb_w * mb_h * 4; for (i = 0; i < 3; i++) c->prev_dc[i] = 1024; bx = by = 0; c->bdsp.clear_blocks(c->block[0]); for (mb_y = 0; mb_y < mb_h; mb_y++) { for (mb_x = 0; mb_x < mb_w; mb_x++) { if (mask && !mask[mb_x * 2] && !mask[mb_x * 2 + 1] && !mask[mb_x * 2 + mask_stride] && !mask[mb_x * 2 + 1 + mask_stride]) { bx += 16; continue; } for (j = 0; j < 2; j++) { for (i = 0; i < 2; i++) { if (mask && !mask[mb_x * 2 + i + j * mask_stride]) continue; num_mbs--; if ((ret = jpg_decode_block(c, &gb, 0, c->block[i + j * 2])) != 0) return ret; c->idsp.idct(c->block[i + j * 2]); } } for (i = 1; i < 3; i++) { if ((ret = jpg_decode_block(c, &gb, i, c->block[i + 3])) != 0) return ret; c->idsp.idct(c->block[i + 3]); } for (j = 0; j < 16; j++) { uint8_t *out = dst + bx * 3 + (by + j) * dst_stride; for (i = 0; i < 16; i++) { int Y, U, V; Y = c->block[(j >> 3) * 2 + (i >> 3)][(i & 7) + (j & 7) * 8]; U = c->block[4][(i >> 1) + (j >> 1) * 8] - 128; V = c->block[5][(i >> 1) + (j >> 1) * 8] - 128; yuv2rgb(out + i * 3, ridx, Y, U, V); } } if (!num_mbs) return 0; bx += 16; } bx = 0; by += 16; if (mask) mask += mask_stride * 2; } return 0; } #define LOAD_NEIGHBOURS(x) \ W = curr_row[(x) - 1]; \ N = above_row[(x)]; \ WW = curr_row[(x) - 2]; \ NW = above_row[(x) - 1]; \ NE = above_row[(x) + 1]; \ NN = above2_row[(x)]; \ NNW = above2_row[(x) - 1]; \ NWW = above_row[(x) - 2]; \ NNE = above2_row[(x) + 1] #define UPDATE_NEIGHBOURS(x) \ NNW = NN; \ NN = NNE; \ NWW = NW; \ NW = N; \ N = NE; \ NE = above_row[(x) + 1]; \ NNE = above2_row[(x) + 1] #define R_shift 16 #define G_shift 8 #define B_shift 0 /* improved djb2 hash from http://www.cse.yorku.ca/~oz/hash.html */ static int djb2_hash(uint32_t key) { uint32_t h = 5381; h = (h * 33) ^ ((key >> 24) & 0xFF); // xxx: probably not needed at all h = (h * 33) ^ ((key >> 16) & 0xFF); h = (h * 33) ^ ((key >> 8) & 0xFF); h = (h * 33) ^ (key & 0xFF); return h & (EPIC_HASH_SIZE - 1); } static void epic_hash_init(ePICPixHash *hash) { memset(hash, 0, sizeof(*hash)); } static ePICPixHashElem *epic_hash_find(const ePICPixHash *hash, uint32_t key) { int i, idx = djb2_hash(key); ePICPixHashElem *bucket = hash->bucket[idx]; for (i = 0; i < hash->bucket_fill[idx]; i++) if (bucket[i].pix_id == key) return &bucket[i]; return NULL; } static ePICPixHashElem *epic_hash_add(ePICPixHash *hash, uint32_t key) { ePICPixHashElem *bucket, *ret; int idx = djb2_hash(key); if (hash->bucket_size[idx] > INT_MAX / sizeof(**hash->bucket)) return NULL; if (!(hash->bucket_fill[idx] < hash->bucket_size[idx])) { int new_size = hash->bucket_size[idx] + 16; bucket = av_realloc(hash->bucket[idx], new_size * sizeof(*bucket)); if (!bucket) return NULL; hash->bucket[idx] = bucket; hash->bucket_size[idx] = new_size; } ret = &hash->bucket[idx][hash->bucket_fill[idx]++]; memset(ret, 0, sizeof(*ret)); ret->pix_id = key; return ret; } static int epic_add_pixel_to_cache(ePICPixHash *hash, uint32_t key, uint32_t pix) { ePICPixListElem *new_elem; ePICPixHashElem *hash_elem = epic_hash_find(hash, key); if (!hash_elem) { if (!(hash_elem = epic_hash_add(hash, key))) return AVERROR(ENOMEM); } new_elem = av_mallocz(sizeof(*new_elem)); if (!new_elem) return AVERROR(ENOMEM); new_elem->pixel = pix; new_elem->next = hash_elem->list; hash_elem->list = new_elem; return 0; } static inline int epic_cache_entries_for_pixel(const ePICPixHash *hash, uint32_t pix) { ePICPixHashElem *hash_elem = epic_hash_find(hash, pix); if (hash_elem != NULL && hash_elem->list != NULL) return 1; return 0; } static void epic_free_pixel_cache(ePICPixHash *hash) { int i, j; for (i = 0; i < EPIC_HASH_SIZE; i++) { for (j = 0; j < hash->bucket_fill[i]; j++) { ePICPixListElem *list_elem = hash->bucket[i][j].list; while (list_elem) { ePICPixListElem *tmp = list_elem->next; av_free(list_elem); list_elem = tmp; } } av_freep(&hash->bucket[i]); hash->bucket_size[i] = hash->bucket_fill[i] = 0; } } static inline int is_pixel_on_stack(const ePICContext *dc, uint32_t pix) { int i; for (i = 0; i < dc->stack_pos; i++) if (dc->stack[i] == pix) break; return i != dc->stack_pos; } #define TOSIGNED(val) (((val) >> 1) ^ -((val) & 1)) static inline int epic_decode_component_pred(ePICContext *dc, int N, int W, int NW) { unsigned delta = ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung); return mid_pred(N, N + W - NW, W) - TOSIGNED(delta); } static uint32_t epic_decode_pixel_pred(ePICContext *dc, int x, int y, const uint32_t *curr_row, const uint32_t *above_row) { uint32_t N, W, NW, pred; unsigned delta; int GN, GW, GNW, R, G, B; if (x && y) { W = curr_row[x - 1]; N = above_row[x]; NW = above_row[x - 1]; GN = (N >> G_shift) & 0xFF; GW = (W >> G_shift) & 0xFF; GNW = (NW >> G_shift) & 0xFF; G = epic_decode_component_pred(dc, GN, GW, GNW); R = G + epic_decode_component_pred(dc, ((N >> R_shift) & 0xFF) - GN, ((W >> R_shift) & 0xFF) - GW, ((NW >> R_shift) & 0xFF) - GNW); B = G + epic_decode_component_pred(dc, ((N >> B_shift) & 0xFF) - GN, ((W >> B_shift) & 0xFF) - GW, ((NW >> B_shift) & 0xFF) - GNW); } else { if (x) pred = curr_row[x - 1]; else pred = above_row[x]; delta = ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung); R = ((pred >> R_shift) & 0xFF) - TOSIGNED(delta); delta = ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung); G = ((pred >> G_shift) & 0xFF) - TOSIGNED(delta); delta = ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung); B = ((pred >> B_shift) & 0xFF) - TOSIGNED(delta); } return (R << R_shift) | (G << G_shift) | (B << B_shift); } static int epic_predict_pixel(ePICContext *dc, uint8_t *rung, uint32_t *pPix, uint32_t pix) { if (!ff_els_decode_bit(&dc->els_ctx, rung)) { *pPix = pix; return 1; } dc->stack[dc->stack_pos++ & EPIC_PIX_STACK_MAX] = pix; return 0; } static int epic_handle_edges(ePICContext *dc, int x, int y, const uint32_t *curr_row, const uint32_t *above_row, uint32_t *pPix) { uint32_t pix; if (!x && !y) { /* special case: top-left pixel */ /* the top-left pixel is coded independently with 3 unsigned numbers */ *pPix = (ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung) << R_shift) | (ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung) << G_shift) | (ff_els_decode_unsigned(&dc->els_ctx, &dc->unsigned_rung) << B_shift); return 1; } if (x) { /* predict from W first */ pix = curr_row[x - 1]; if (epic_predict_pixel(dc, &dc->W_flag_rung, pPix, pix)) return 1; } if (y) { /* then try to predict from N */ pix = above_row[x]; if (!dc->stack_pos || dc->stack[0] != pix) { if (epic_predict_pixel(dc, &dc->N_flag_rung, pPix, pix)) return 1; } } return 0; } static int epic_decode_run_length(ePICContext *dc, int x, int y, int tile_width, const uint32_t *curr_row, const uint32_t *above_row, const uint32_t *above2_row, uint32_t *pPix, int *pRun) { int idx, got_pixel = 0, WWneW, old_WWneW = 0; uint32_t W, WW, N, NN, NW, NE, NWW, NNW, NNE; *pRun = 0; LOAD_NEIGHBOURS(x); if (dc->next_run_pos == x) { /* can't reuse W for the new pixel in this case */ WWneW = 1; } else { idx = (WW != W) << 7 | (NW != W) << 6 | (N != NE) << 5 | (NW != N) << 4 | (NWW != NW) << 3 | (NNE != NE) << 2 | (NN != N) << 1 | (NNW != NW); WWneW = ff_els_decode_bit(&dc->els_ctx, &dc->W_ctx_rung[idx]); } if (WWneW) dc->stack[dc->stack_pos++ & EPIC_PIX_STACK_MAX] = W; else { *pPix = W; got_pixel = 1; } do { int NWneW = 1; if (got_pixel) // pixel value already known (derived from either W or N) NWneW = *pPix != N; else { // pixel value is unknown and will be decoded later NWneW = *pRun ? NWneW : NW != W; /* TODO: RFC this mess! */ switch (((NW != N) << 2) | (NWneW << 1) | WWneW) { case 0: break; // do nothing here case 3: case 5: case 6: case 7: if (!is_pixel_on_stack(dc, N)) { idx = WWneW << 8 | (*pRun ? old_WWneW : WW != W) << 7 | NWneW << 6 | (N != NE) << 5 | (NW != N) << 4 | (NWW != NW) << 3 | (NNE != NE) << 2 | (NN != N) << 1 | (NNW != NW); if (!ff_els_decode_bit(&dc->els_ctx, &dc->N_ctx_rung[idx])) { NWneW = 0; *pPix = N; got_pixel = 1; break; } } /* fall through */ default: NWneW = 1; old_WWneW = WWneW; if (!is_pixel_on_stack(dc, N)) dc->stack[dc->stack_pos++ & EPIC_PIX_STACK_MAX] = N; } } (*pRun)++; if (x + *pRun >= tile_width - 1) break; UPDATE_NEIGHBOURS(x + *pRun); if (!NWneW && NW == N && N == NE) { int pos, run, rle; int start_pos = x + *pRun; /* scan for a run of pix in the line above */ uint32_t pix = above_row[start_pos + 1]; for (pos = start_pos + 2; pos < tile_width; pos++) if (!(above_row[pos] == pix)) break; run = pos - start_pos - 1; idx = av_ceil_log2(run); if (ff_els_decode_bit(&dc->els_ctx, &dc->prev_row_rung[idx])) *pRun += run; else { int flag; /* run-length is coded as plain binary number of idx - 1 bits */ for (pos = idx - 1, rle = 0, flag = 0; pos >= 0; pos--) { if ((1 << pos) + rle < run && ff_els_decode_bit(&dc->els_ctx, flag ? &dc->runlen_one : &dc->runlen_zeroes[pos])) { flag = 1; rle |= 1 << pos; } } *pRun += rle; break; // return immediately } if (x + *pRun >= tile_width - 1) break; LOAD_NEIGHBOURS(x + *pRun); WWneW = 0; NWneW = 0; } idx = WWneW << 7 | NWneW << 6 | (N != NE) << 5 | (NW != N) << 4 | (NWW != NW) << 3 | (NNE != NE) << 2 | (NN != N) << 1 | (NNW != NW); WWneW = ff_els_decode_bit(&dc->els_ctx, &dc->W_ctx_rung[idx]); } while (!WWneW); dc->next_run_pos = x + *pRun; return got_pixel; } static int epic_predict_pixel2(ePICContext *dc, uint8_t *rung, uint32_t *pPix, uint32_t pix) { if (ff_els_decode_bit(&dc->els_ctx, rung)) { *pPix = pix; return 1; } dc->stack[dc->stack_pos++ & EPIC_PIX_STACK_MAX] = pix; return 0; } static int epic_predict_from_NW_NE(ePICContext *dc, int x, int y, int run, int tile_width, const uint32_t *curr_row, const uint32_t *above_row, uint32_t *pPix) { int pos; /* try to reuse the NW pixel first */ if (x && y) { uint32_t NW = above_row[x - 1]; if (NW != curr_row[x - 1] && NW != above_row[x] && !is_pixel_on_stack(dc, NW)) { if (epic_predict_pixel2(dc, &dc->nw_pred_rung[NW & 0xFF], pPix, NW)) return 1; } } /* try to reuse the NE[x + run, y] pixel */ pos = x + run - 1; if (pos < tile_width - 1 && y) { uint32_t NE = above_row[pos + 1]; if (NE != above_row[pos] && !is_pixel_on_stack(dc, NE)) { if (epic_predict_pixel2(dc, &dc->ne_pred_rung[NE & 0xFF], pPix, NE)) return 1; } } return 0; } static int epic_decode_from_cache(ePICContext *dc, uint32_t W, uint32_t *pPix) { ePICPixListElem *list, *prev = NULL; ePICPixHashElem *hash_elem = epic_hash_find(&dc->hash, W); if (!hash_elem || !hash_elem->list) return 0; list = hash_elem->list; while (list) { if (!is_pixel_on_stack(dc, list->pixel)) { if (ff_els_decode_bit(&dc->els_ctx, &list->rung)) { *pPix = list->pixel; if (list != hash_elem->list) { prev->next = list->next; list->next = hash_elem->list; hash_elem->list = list; } return 1; } dc->stack[dc->stack_pos++ & EPIC_PIX_STACK_MAX] = list->pixel; } prev = list; list = list->next; } return 0; } static int epic_decode_tile(ePICContext *dc, uint8_t *out, int tile_height, int tile_width, int stride) { int x, y; uint32_t pix; uint32_t *curr_row = NULL, *above_row = NULL, *above2_row; for (y = 0; y < tile_height; y++, out += stride) { above2_row = above_row; above_row = curr_row; curr_row = (uint32_t *) out; for (x = 0, dc->next_run_pos = 0; x < tile_width;) { if (dc->els_ctx.err) return AVERROR_INVALIDDATA; // bail out in the case of ELS overflow pix = curr_row[x - 1]; // get W pixel if (y >= 1 && x >= 2 && pix != curr_row[x - 2] && pix != above_row[x - 1] && pix != above_row[x - 2] && pix != above_row[x] && !epic_cache_entries_for_pixel(&dc->hash, pix)) { curr_row[x] = epic_decode_pixel_pred(dc, x, y, curr_row, above_row); x++; } else { int got_pixel, run; dc->stack_pos = 0; // empty stack if (y < 2 || x < 2 || x == tile_width - 1) { run = 1; got_pixel = epic_handle_edges(dc, x, y, curr_row, above_row, &pix); } else got_pixel = epic_decode_run_length(dc, x, y, tile_width, curr_row, above_row, above2_row, &pix, &run); if (!got_pixel && !epic_predict_from_NW_NE(dc, x, y, run, tile_width, curr_row, above_row, &pix)) { uint32_t ref_pix = curr_row[x - 1]; if (!x || !epic_decode_from_cache(dc, ref_pix, &pix)) { pix = epic_decode_pixel_pred(dc, x, y, curr_row, above_row); if (x) { int ret = epic_add_pixel_to_cache(&dc->hash, ref_pix, pix); if (ret) return ret; } } } for (; run > 0; x++, run--) curr_row[x] = pix; } } } return 0; } static int epic_jb_decode_tile(G2MContext *c, int tile_x, int tile_y, const uint8_t *src, size_t src_size, AVCodecContext *avctx) { uint8_t prefix, mask = 0x80; int extrabytes, tile_width, tile_height, awidth, aheight; size_t els_dsize; uint8_t *dst; if (!src_size) return 0; /* get data size of the ELS partition as unsigned variable-length integer */ prefix = *src++; src_size--; for (extrabytes = 0; (prefix & mask) && (extrabytes < 7); extrabytes++) mask >>= 1; if (extrabytes > 3 || src_size < extrabytes) { av_log(avctx, AV_LOG_ERROR, "ePIC: invalid data size VLI\n"); return AVERROR_INVALIDDATA; } els_dsize = prefix & ((0x80 >> extrabytes) - 1); // mask out the length prefix while (extrabytes-- > 0) { els_dsize = (els_dsize << 8) | *src++; src_size--; } if (src_size < els_dsize) { av_log(avctx, AV_LOG_ERROR, "ePIC: data too short, needed %zu, got %zu\n", els_dsize, src_size); return AVERROR_INVALIDDATA; } tile_width = FFMIN(c->width - tile_x * c->tile_width, c->tile_width); tile_height = FFMIN(c->height - tile_y * c->tile_height, c->tile_height); awidth = FFALIGN(tile_width, 16); aheight = FFALIGN(tile_height, 16); if (els_dsize) { int ret, i, j, k; uint8_t tr_r, tr_g, tr_b, *buf; uint32_t *in; /* ELS decoder initializations */ memset(&c->ec, 0, sizeof(c->ec)); ff_els_decoder_init(&c->ec.els_ctx, src, els_dsize); epic_hash_init(&c->ec.hash); /* decode transparent pixel value */ tr_r = ff_els_decode_unsigned(&c->ec.els_ctx, &c->ec.unsigned_rung); tr_g = ff_els_decode_unsigned(&c->ec.els_ctx, &c->ec.unsigned_rung); tr_b = ff_els_decode_unsigned(&c->ec.els_ctx, &c->ec.unsigned_rung); if (c->ec.els_ctx.err != 0) { av_log(avctx, AV_LOG_ERROR, "ePIC: couldn't decode transparency pixel!\n"); return AVERROR_INVALIDDATA; } ret = epic_decode_tile(&c->ec, c->epic_buf, tile_height, tile_width, c->epic_buf_stride); epic_free_pixel_cache(&c->ec.hash); ff_els_decoder_uninit(&c->ec.unsigned_rung); if (ret) { av_log(avctx, AV_LOG_ERROR, "ePIC: tile decoding failed, frame=%d, tile_x=%d, tile_y=%d\n", avctx->frame_number, tile_x, tile_y); return AVERROR_INVALIDDATA; } buf = c->epic_buf; dst = c->framebuf + tile_x * c->tile_width * 3 + tile_y * c->tile_height * c->framebuf_stride; for (j = 0; j < tile_height; j++) { uint8_t *out = dst; in = (uint32_t *) buf; for (i = 0; i < tile_width; i++) { out[0] = (in[i] >> R_shift) & 0xFF; out[1] = (in[i] >> G_shift) & 0xFF; out[2] = (in[i] >> B_shift) & 0xFF; out += 3; } buf += c->epic_buf_stride; dst += c->framebuf_stride; } if (src_size > els_dsize) { uint8_t *jpg; uint32_t tr; int bstride = FFALIGN(tile_width, 16) >> 3; int nblocks = 0; int estride = c->epic_buf_stride >> 2; src += els_dsize; src_size -= els_dsize; in = (uint32_t *) c->epic_buf; tr = (tr_r << R_shift) | (tr_g << G_shift) | (tr_b << B_shift); memset(c->kempf_flags, 0, (aheight >> 3) * bstride * sizeof(*c->kempf_flags)); for (j = 0; j < tile_height; j += 8) { for (i = 0; i < tile_width; i += 8) { c->kempf_flags[(i >> 3) + (j >> 3) * bstride] = 0; for (k = 0; k < 8 * 8; k++) { if (in[i + (k & 7) + (k >> 3) * estride] == tr) { c->kempf_flags[(i >> 3) + (j >> 3) * bstride] = 1; nblocks++; break; } } } in += 8 * estride; } memset(c->jpeg_tile, 0, c->tile_stride * aheight); jpg_decode_data(&c->jc, awidth, aheight, src, src_size, c->jpeg_tile, c->tile_stride, c->kempf_flags, bstride, nblocks, c->swapuv); in = (uint32_t *) c->epic_buf; dst = c->framebuf + tile_x * c->tile_width * 3 + tile_y * c->tile_height * c->framebuf_stride; jpg = c->jpeg_tile; for (j = 0; j < tile_height; j++) { for (i = 0; i < tile_width; i++) if (in[i] == tr) memcpy(dst + i * 3, jpg + i * 3, 3); in += c->epic_buf_stride >> 2; dst += c->framebuf_stride; jpg += c->tile_stride; } } } else { dst = c->framebuf + tile_x * c->tile_width * 3 + tile_y * c->tile_height * c->framebuf_stride; return jpg_decode_data(&c->jc, tile_width, tile_height, src, src_size, dst, c->framebuf_stride, NULL, 0, 0, c->swapuv); } return 0; } static void kempf_restore_buf(const uint8_t *src, int len, uint8_t *dst, int stride, const uint8_t *jpeg_tile, int tile_stride, int width, int height, const uint8_t *pal, int npal, int tidx) { GetBitContext gb; int i, j, nb, col; int align_width = FFALIGN(width, 16); init_get_bits(&gb, src, len * 8); if (npal <= 2) nb = 1; else if (npal <= 4) nb = 2; else if (npal <= 16) nb = 4; else nb = 8; for (j = 0; j < height; j++, dst += stride, jpeg_tile += tile_stride) { if (get_bits(&gb, 8)) continue; for (i = 0; i < width; i++) { col = get_bits(&gb, nb); if (col != tidx) memcpy(dst + i * 3, pal + col * 3, 3); else memcpy(dst + i * 3, jpeg_tile + i * 3, 3); } skip_bits_long(&gb, nb * (align_width - width)); } } static int kempf_decode_tile(G2MContext *c, int tile_x, int tile_y, const uint8_t *src, int src_size) { int width, height; int hdr, zsize, npal, tidx = -1, ret; int i, j; const uint8_t *src_end = src + src_size; uint8_t pal[768], transp[3]; uLongf dlen = (c->tile_width + 1) * c->tile_height; int sub_type; int nblocks, cblocks, bstride; int bits, bitbuf, coded; uint8_t *dst = c->framebuf + tile_x * c->tile_width * 3 + tile_y * c->tile_height * c->framebuf_stride; if (src_size < 2) return AVERROR_INVALIDDATA; width = FFMIN(c->width - tile_x * c->tile_width, c->tile_width); height = FFMIN(c->height - tile_y * c->tile_height, c->tile_height); hdr = *src++; sub_type = hdr >> 5; if (sub_type == 0) { int j; memcpy(transp, src, 3); src += 3; for (j = 0; j < height; j++, dst += c->framebuf_stride) for (i = 0; i < width; i++) memcpy(dst + i * 3, transp, 3); return 0; } else if (sub_type == 1) { return jpg_decode_data(&c->jc, width, height, src, src_end - src, dst, c->framebuf_stride, NULL, 0, 0, 0); } if (sub_type != 2) { memcpy(transp, src, 3); src += 3; } npal = *src++ + 1; memcpy(pal, src, npal * 3); src += npal * 3; if (sub_type != 2) { for (i = 0; i < npal; i++) { if (!memcmp(pal + i * 3, transp, 3)) { tidx = i; break; } } } if (src_end - src < 2) return 0; zsize = (src[0] << 8) | src[1]; src += 2; if (src_end - src < zsize) return AVERROR_INVALIDDATA; ret = uncompress(c->kempf_buf, &dlen, src, zsize); if (ret) return AVERROR_INVALIDDATA; src += zsize; if (sub_type == 2) { kempf_restore_buf(c->kempf_buf, dlen, dst, c->framebuf_stride, NULL, 0, width, height, pal, npal, tidx); return 0; } nblocks = *src++ + 1; cblocks = 0; bstride = FFALIGN(width, 16) >> 3; // blocks are coded LSB and we need normal bitreader for JPEG data bits = 0; for (i = 0; i < (FFALIGN(height, 16) >> 4); i++) { for (j = 0; j < (FFALIGN(width, 16) >> 4); j++) { if (!bits) { bitbuf = *src++; bits = 8; } coded = bitbuf & 1; bits--; bitbuf >>= 1; cblocks += coded; if (cblocks > nblocks) return AVERROR_INVALIDDATA; c->kempf_flags[j * 2 + i * 2 * bstride] = c->kempf_flags[j * 2 + 1 + i * 2 * bstride] = c->kempf_flags[j * 2 + (i * 2 + 1) * bstride] = c->kempf_flags[j * 2 + 1 + (i * 2 + 1) * bstride] = coded; } } memset(c->jpeg_tile, 0, c->tile_stride * height); jpg_decode_data(&c->jc, width, height, src, src_end - src, c->jpeg_tile, c->tile_stride, c->kempf_flags, bstride, nblocks * 4, 0); kempf_restore_buf(c->kempf_buf, dlen, dst, c->framebuf_stride, c->jpeg_tile, c->tile_stride, width, height, pal, npal, tidx); return 0; } static int g2m_init_buffers(G2MContext *c) { int aligned_height; if (!c->framebuf || c->old_width < c->width || c->old_height < c->height) { c->framebuf_stride = FFALIGN(c->width * 3, 16); aligned_height = FFALIGN(c->height, 16); av_free(c->framebuf); c->framebuf = av_mallocz(c->framebuf_stride * aligned_height); if (!c->framebuf) return AVERROR(ENOMEM); } if (!c->synth_tile || !c->jpeg_tile || (c->compression == 2 && !c->epic_buf_base) || c->old_tile_w < c->tile_width || c->old_tile_h < c->tile_height) { c->tile_stride = FFALIGN(c->tile_width * 3, 16); c->epic_buf_stride = FFALIGN(c->tile_width * 4, 16); aligned_height = FFALIGN(c->tile_height, 16); av_free(c->synth_tile); av_free(c->jpeg_tile); av_free(c->kempf_buf); av_free(c->kempf_flags); av_free(c->epic_buf_base); c->synth_tile = av_mallocz(c->tile_stride * aligned_height); c->jpeg_tile = av_mallocz(c->tile_stride * aligned_height); c->kempf_buf = av_mallocz((c->tile_width + 1) * aligned_height + AV_INPUT_BUFFER_PADDING_SIZE); c->kempf_flags = av_mallocz(c->tile_width * aligned_height); if (!c->synth_tile || !c->jpeg_tile || !c->kempf_buf || !c->kempf_flags) return AVERROR(ENOMEM); if (c->compression == 2) { c->epic_buf_base = av_mallocz(c->epic_buf_stride * aligned_height + 4); if (!c->epic_buf_base) return AVERROR(ENOMEM); c->epic_buf = c->epic_buf_base + 4; } } return 0; } static int g2m_load_cursor(AVCodecContext *avctx, G2MContext *c, GetByteContext *gb) { int i, j, k; uint8_t *dst; uint32_t bits; uint32_t cur_size, cursor_w, cursor_h, cursor_stride; uint32_t cursor_hot_x, cursor_hot_y; int cursor_fmt, err; cur_size = bytestream2_get_be32(gb); cursor_w = bytestream2_get_byte(gb); cursor_h = bytestream2_get_byte(gb); cursor_hot_x = bytestream2_get_byte(gb); cursor_hot_y = bytestream2_get_byte(gb); cursor_fmt = bytestream2_get_byte(gb); cursor_stride = FFALIGN(cursor_w, 32) * 4; if (cursor_w < 1 || cursor_w > 256 || cursor_h < 1 || cursor_h > 256) { av_log(avctx, AV_LOG_ERROR, "Invalid cursor dimensions %"PRIu32"x%"PRIu32"\n", cursor_w, cursor_h); return AVERROR_INVALIDDATA; } if (cursor_hot_x > cursor_w || cursor_hot_y > cursor_h) { av_log(avctx, AV_LOG_WARNING, "Invalid hotspot position %"PRIu32",%"PRIu32"\n", cursor_hot_x, cursor_hot_y); cursor_hot_x = FFMIN(cursor_hot_x, cursor_w - 1); cursor_hot_y = FFMIN(cursor_hot_y, cursor_h - 1); } if (cur_size - 9 > bytestream2_get_bytes_left(gb) || c->cursor_w * c->cursor_h / 4 > cur_size) { av_log(avctx, AV_LOG_ERROR, "Invalid cursor data size %"PRIu32"/%u\n", cur_size, bytestream2_get_bytes_left(gb)); return AVERROR_INVALIDDATA; } if (cursor_fmt != 1 && cursor_fmt != 32) { avpriv_report_missing_feature(avctx, "Cursor format %d", cursor_fmt); return AVERROR_PATCHWELCOME; } if ((err = av_reallocp(&c->cursor, cursor_stride * cursor_h)) < 0) { av_log(avctx, AV_LOG_ERROR, "Cannot allocate cursor buffer\n"); return err; } c->cursor_w = cursor_w; c->cursor_h = cursor_h; c->cursor_hot_x = cursor_hot_x; c->cursor_hot_y = cursor_hot_y; c->cursor_fmt = cursor_fmt; c->cursor_stride = cursor_stride; dst = c->cursor; switch (c->cursor_fmt) { case 1: // old monochrome for (j = 0; j < c->cursor_h; j++) { for (i = 0; i < c->cursor_w; i += 32) { bits = bytestream2_get_be32(gb); for (k = 0; k < 32; k++) { dst[0] = !!(bits & 0x80000000); dst += 4; bits <<= 1; } } dst += c->cursor_stride - c->cursor_w * 4; } dst = c->cursor; for (j = 0; j < c->cursor_h; j++) { for (i = 0; i < c->cursor_w; i += 32) { bits = bytestream2_get_be32(gb); 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 += c->cursor_stride - c->cursor_w * 4; } break; case 32: // full colour /* skip monochrome version of the cursor and decode RGBA instead */ bytestream2_skip(gb, c->cursor_h * (FFALIGN(c->cursor_w, 32) >> 3)); for (j = 0; j < c->cursor_h; j++) { for (i = 0; i < c->cursor_w; i++) { int val = bytestream2_get_be32(gb); *dst++ = val >> 0; *dst++ = val >> 8; *dst++ = val >> 16; *dst++ = val >> 24; } dst += c->cursor_stride - c->cursor_w * 4; } break; default: return AVERROR_PATCHWELCOME; } return 0; } #define APPLY_ALPHA(src, new, alpha) \ src = (src * (256 - alpha) + new * alpha) >> 8 static void g2m_paint_cursor(G2MContext *c, uint8_t *dst, int stride) { int i, j; int x, y, w, h; const uint8_t *cursor; if (!c->cursor) return; x = c->cursor_x - c->cursor_hot_x; y = c->cursor_y - c->cursor_hot_y; cursor = c->cursor; w = c->cursor_w; h = c->cursor_h; if (x + w > c->width) w = c->width - x; if (y + h > c->height) h = c->height - y; if (x < 0) { w += x; cursor += -x * 4; } else { dst += x * 3; } if (y < 0) { h += y; cursor += -y * c->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 += c->cursor_stride; } } static int g2m_decode_frame(AVCodecContext *avctx, void *data, int *got_picture_ptr, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; G2MContext *c = avctx->priv_data; AVFrame *pic = data; GetByteContext bc, tbc; int magic; int got_header = 0; uint32_t chunk_size, r_mask, g_mask, b_mask; int chunk_type, chunk_start; int i; int ret; if (buf_size < 12) { av_log(avctx, AV_LOG_ERROR, "Frame should have at least 12 bytes, got %d instead\n", buf_size); return AVERROR_INVALIDDATA; } bytestream2_init(&bc, buf, buf_size); magic = bytestream2_get_be32(&bc); if ((magic & ~0xF) != MKBETAG('G', '2', 'M', '0') || (magic & 0xF) < 2 || (magic & 0xF) > 5) { av_log(avctx, AV_LOG_ERROR, "Wrong magic %08X\n", magic); return AVERROR_INVALIDDATA; } c->swapuv = magic == MKBETAG('G', '2', 'M', '2'); while (bytestream2_get_bytes_left(&bc) > 5) { chunk_size = bytestream2_get_le32(&bc) - 1; chunk_type = bytestream2_get_byte(&bc); chunk_start = bytestream2_tell(&bc); if (chunk_size > bytestream2_get_bytes_left(&bc)) { av_log(avctx, AV_LOG_ERROR, "Invalid chunk size %"PRIu32" type %02X\n", chunk_size, chunk_type); break; } switch (chunk_type) { case DISPLAY_INFO: c->got_header = 0; if (chunk_size < 21) { av_log(avctx, AV_LOG_ERROR, "Invalid display info size %"PRIu32"\n", chunk_size); break; } c->width = bytestream2_get_be32(&bc); c->height = bytestream2_get_be32(&bc); if (c->width < 16 || c->height < 16) { av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d\n", c->width, c->height); ret = AVERROR_INVALIDDATA; goto header_fail; } if (c->width != avctx->width || c->height != avctx->height) { ret = ff_set_dimensions(avctx, c->width, c->height); if (ret < 0) return ret; } c->compression = bytestream2_get_be32(&bc); if (c->compression != 2 && c->compression != 3) { avpriv_report_missing_feature(avctx, "Compression method %d", c->compression); return AVERROR_PATCHWELCOME; } c->tile_width = bytestream2_get_be32(&bc); c->tile_height = bytestream2_get_be32(&bc); if (!c->tile_width || !c->tile_height || ((c->tile_width | c->tile_height) & 0xF)) { av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions %dx%d\n", c->tile_width, c->tile_height); ret = AVERROR_INVALIDDATA; goto header_fail; } c->tiles_x = (c->width + c->tile_width - 1) / c->tile_width; c->tiles_y = (c->height + c->tile_height - 1) / c->tile_height; c->bpp = bytestream2_get_byte(&bc); if (c->bpp == 32) { if (bytestream2_get_bytes_left(&bc) < 16 || (chunk_size - 21) < 16) { av_log(avctx, AV_LOG_ERROR, "Display info: missing bitmasks!\n"); return AVERROR_INVALIDDATA; } r_mask = bytestream2_get_be32(&bc); g_mask = bytestream2_get_be32(&bc); b_mask = bytestream2_get_be32(&bc); if (r_mask != 0xFF0000 || g_mask != 0xFF00 || b_mask != 0xFF) { avpriv_report_missing_feature(avctx, "Bitmasks: R=%"PRIX32", G=%"PRIX32", B=%"PRIX32, r_mask, g_mask, b_mask); return AVERROR_PATCHWELCOME; } } else { avpriv_request_sample(avctx, "bpp=%d", c->bpp); return AVERROR_PATCHWELCOME; } if (g2m_init_buffers(c)) { ret = AVERROR(ENOMEM); goto header_fail; } got_header = 1; break; case TILE_DATA: if (!c->tiles_x || !c->tiles_y) { av_log(avctx, AV_LOG_WARNING, "No display info - skipping tile\n"); break; } if (chunk_size < 2) { av_log(avctx, AV_LOG_ERROR, "Invalid tile data size %"PRIu32"\n", chunk_size); break; } c->tile_x = bytestream2_get_byte(&bc); c->tile_y = bytestream2_get_byte(&bc); if (c->tile_x >= c->tiles_x || c->tile_y >= c->tiles_y) { av_log(avctx, AV_LOG_ERROR, "Invalid tile pos %d,%d (in %dx%d grid)\n", c->tile_x, c->tile_y, c->tiles_x, c->tiles_y); break; } ret = 0; switch (c->compression) { case COMPR_EPIC_J_B: ret = epic_jb_decode_tile(c, c->tile_x, c->tile_y, buf + bytestream2_tell(&bc), chunk_size - 2, avctx); break; case COMPR_KEMPF_J_B: ret = kempf_decode_tile(c, c->tile_x, c->tile_y, buf + bytestream2_tell(&bc), chunk_size - 2); break; } if (ret && c->framebuf) av_log(avctx, AV_LOG_ERROR, "Error decoding tile %d,%d\n", c->tile_x, c->tile_y); break; case CURSOR_POS: if (chunk_size < 5) { av_log(avctx, AV_LOG_ERROR, "Invalid cursor pos size %"PRIu32"\n", chunk_size); break; } c->cursor_x = bytestream2_get_be16(&bc); c->cursor_y = bytestream2_get_be16(&bc); break; case CURSOR_SHAPE: if (chunk_size < 8) { av_log(avctx, AV_LOG_ERROR, "Invalid cursor data size %"PRIu32"\n", chunk_size); break; } bytestream2_init(&tbc, buf + bytestream2_tell(&bc), chunk_size - 4); g2m_load_cursor(avctx, c, &tbc); break; case CHUNK_CC: case CHUNK_CD: break; default: av_log(avctx, AV_LOG_WARNING, "Skipping chunk type %02d\n", chunk_type); } /* navigate to next chunk */ bytestream2_skip(&bc, chunk_start + chunk_size - bytestream2_tell(&bc)); } if (got_header) c->got_header = 1; if (c->width && c->height) { if ((ret = ff_get_buffer(avctx, pic, 0)) < 0) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return ret; } pic->key_frame = got_header; pic->pict_type = got_header ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P; for (i = 0; i < avctx->height; i++) memcpy(pic->data[0] + i * pic->linesize[0], c->framebuf + i * c->framebuf_stride, c->width * 3); g2m_paint_cursor(c, pic->data[0], pic->linesize[0]); *got_picture_ptr = 1; } return buf_size; header_fail: c->width = c->height = 0; c->tiles_x = c->tiles_y = 0; return ret; } static av_cold int g2m_decode_init(AVCodecContext *avctx) { G2MContext *const c = avctx->priv_data; int ret; if ((ret = jpg_init(avctx, &c->jc)) != 0) { av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n"); jpg_free_context(&c->jc); return AVERROR(ENOMEM); } avctx->pix_fmt = AV_PIX_FMT_RGB24; // store original sizes and check against those if resize happens c->orig_width = avctx->width; c->orig_height = avctx->height; return 0; } static av_cold int g2m_decode_end(AVCodecContext *avctx) { G2MContext *const c = avctx->priv_data; jpg_free_context(&c->jc); av_freep(&c->epic_buf_base); av_freep(&c->kempf_buf); av_freep(&c->kempf_flags); av_freep(&c->synth_tile); av_freep(&c->jpeg_tile); av_freep(&c->cursor); av_freep(&c->framebuf); return 0; } AVCodec ff_g2m_decoder = { .name = "g2m", .long_name = NULL_IF_CONFIG_SMALL("Go2Meeting"), .type = AVMEDIA_TYPE_VIDEO, .id = AV_CODEC_ID_G2M, .priv_data_size = sizeof(G2MContext), .init = g2m_decode_init, .close = g2m_decode_end, .decode = g2m_decode_frame, .capabilities = AV_CODEC_CAP_DR1, .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, };