[FFmpeg-devel] [PATCH 78/80] avcodec/mpegvideo: Move packed-b-frames stuff to H263DecContext

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Thu Feb 3 03:06:29 EET 2022


It is only used by the MPEG-4 decoder, yet it is used in
the common H.263-code (i.e. in libavcodec/h263dec.c) and
can therefore not be put in Mpeg4DecContext. Yet moving
it to H263DecContext is possible.

Given that this is nevertheless an MPEG-4 only field,
it is kept in sync in the MPEG-4-decoder's update_thread_context
and not in a (currently inexisting) update_thread_context for
H.263 decoders.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
 libavcodec/h263dec.c       | 27 ++++++++-------
 libavcodec/h263dec.h       |  6 ++++
 libavcodec/mpeg4videodec.c | 70 +++++++++++++++++++++++++++-----------
 libavcodec/mpegvideo.c     |  5 ---
 libavcodec/mpegvideo.h     |  6 ----
 libavcodec/mpegvideo_dec.c | 24 -------------
 libavcodec/nvdec_mpeg4.c   |  2 +-
 7 files changed, 73 insertions(+), 67 deletions(-)

diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index db03e04143..3b0ebbdf9b 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -160,9 +160,12 @@ av_cold int ff_h263_decode_init(AVCodecContext *avctx)
 
 av_cold int ff_h263_decode_end(AVCodecContext *avctx)
 {
-    MPVMainDecContext *const s = avctx->priv_data;
+    H263DecContext *const h263 = avctx->priv_data;
 
-    ff_mpv_common_end(s);
+    av_freep(&h263->bitstream_buffer);
+    h263->allocated_bitstream_buffer_size = 0;
+
+    ff_mpv_common_end(&h263->m);
     return 0;
 }
 
@@ -174,7 +177,7 @@ static int get_consumed_bytes(H263DecContext *h, int buf_size)
     MPVDecContext *const s = &h->m.s;
     int pos = (get_bits_count(&s->gb) + 7) >> 3;
 
-    if (s->divx_packed || s->avctx->hwaccel) {
+    if (h->divx_packed || s->avctx->hwaccel) {
         /* We would have to scan through the whole buf to handle the weird
          * reordering ... */
         return buf_size;
@@ -481,26 +484,26 @@ int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
 #endif
 
 retry:
-    if (s->divx_packed && s->bitstream_buffer_size) {
+    if (h->divx_packed && h->bitstream_buffer_size) {
         int i;
         for(i=0; i < buf_size-3; i++) {
             if (buf[i]==0 && buf[i+1]==0 && buf[i+2]==1) {
                 if (buf[i+3]==0xB0) {
                     av_log(s->avctx, AV_LOG_WARNING, "Discarding excessive bitstream in packed xvid\n");
-                    s->bitstream_buffer_size = 0;
+                    h->bitstream_buffer_size = 0;
                 }
                 break;
             }
         }
     }
 
-    if (s->bitstream_buffer_size && (s->divx_packed || buf_size <= MAX_NVOP_SIZE)) // divx 5.01+/xvid frame reorder
-        ret = init_get_bits8(&s->gb, s->bitstream_buffer,
-                             s->bitstream_buffer_size);
+    if (h->bitstream_buffer_size && (h->divx_packed || buf_size <= MAX_NVOP_SIZE)) // divx 5.01+/xvid frame reorder
+        ret = init_get_bits8(&s->gb, h->bitstream_buffer,
+                             h->bitstream_buffer_size);
     else
         ret = init_get_bits8(&s->gb, buf, buf_size);
 
-    s->bitstream_buffer_size = 0;
+    h->bitstream_buffer_size = 0;
     if (ret < 0)
         return ret;
 
@@ -625,7 +628,7 @@ retry:
     if ((ret = ff_mpv_frame_start(m, avctx)) < 0)
         return ret;
 
-    if (!s->divx_packed && !avctx->hwaccel)
+    if (!h->divx_packed && !avctx->hwaccel)
         ff_thread_finish_setup(avctx);
 
     if (avctx->hwaccel) {
@@ -679,7 +682,7 @@ retry:
             ff_msmpeg4_decode_ext_header(h, buf_size) < 0)
             s->er.error_status_table[s->mb_num - 1] = ER_MB_ERROR;
 
-    av_assert1(s->bitstream_buffer_size == 0);
+    av_assert1(h->bitstream_buffer_size == 0);
 frame_end:
     if (!s->studio_profile)
         ff_er_frame_end(&s->er);
@@ -695,7 +698,7 @@ frame_end:
     if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4)
         ff_mpeg4_frame_end(avctx, buf, buf_size);
 
-    if (!s->divx_packed && avctx->hwaccel)
+    if (!h->divx_packed && avctx->hwaccel)
         ff_thread_finish_setup(avctx);
 
     av_assert1(s->current_picture.f->pict_type == s->current_picture_ptr->f->pict_type);
diff --git a/libavcodec/h263dec.h b/libavcodec/h263dec.h
index 7eebffc91c..04c238d90a 100644
--- a/libavcodec/h263dec.h
+++ b/libavcodec/h263dec.h
@@ -47,6 +47,12 @@ typedef struct H263DecContext {
     int pb_frame;          ///< PB-frame mode (0 = none, 1 = base, 2 = improved)
     int long_vectors;      ///< use horrible H.263v1 long vector mode
     int ehc_mode;
+
+    /* divx specific, used to workaround (many) bugs in divx5 */
+    int divx_packed;
+    uint8_t *bitstream_buffer; //Divx 5.01 puts several frames in a single one, this is used to reorder them
+    int bitstream_buffer_size;
+    unsigned int allocated_bitstream_buffer_size;
 } H263DecContext;
 
 int ff_h263_decode_motion(MPVDecContext *s, int pred, int f_code);
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index 7e3b672312..2d1463d564 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -2774,7 +2774,7 @@ static int decode_user_data(Mpeg4DecContext *ctx, GetBitContext *gb)
     if (e >= 2) {
         ctx->divx_version = ver;
         ctx->divx_build   = build;
-        s->divx_packed  = e == 3 && last == 'p';
+        h->divx_packed    = e == 3 && last == 'p';
     }
 
     /* libavcodec detection */
@@ -2811,7 +2811,8 @@ static int decode_user_data(Mpeg4DecContext *ctx, GetBitContext *gb)
 int ff_mpeg4_workaround_bugs(AVCodecContext *avctx)
 {
     Mpeg4DecContext *ctx = avctx->priv_data;
-    MPVMainDecContext *const m = &ctx->h.m;
+    H263DecContext *const h = &ctx->h;
+    MPVMainDecContext *const m = &h->m;
     MPVDecContext *const s = &m->s;
 
     if (ctx->xvid_build == -1 && ctx->divx_version == -1 && ctx->lavc_build == -1) {
@@ -2914,7 +2915,7 @@ int ff_mpeg4_workaround_bugs(AVCodecContext *avctx)
         av_log(s->avctx, AV_LOG_DEBUG,
                "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
                s->workaround_bugs, ctx->lavc_build, ctx->xvid_build,
-               ctx->divx_version, ctx->divx_build, s->divx_packed ? "p" : "");
+               ctx->divx_version, ctx->divx_build, h->divx_packed ? "p" : "");
 
     if (CONFIG_MPEG4_DECODER && ctx->xvid_build >= 0 &&
         s->codec_id == AV_CODEC_ID_MPEG4 &&
@@ -3486,8 +3487,8 @@ int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
     /* divx 5.01+ bitstream reorder stuff */
     /* Since this clobbers the input buffer and hwaccel codecs still need the
      * data during hwaccel->end_frame we should not do this any earlier */
-    if (s->divx_packed) {
-        int current_pos     = s->gb.buffer == s->bitstream_buffer ? 0 : (get_bits_count(&s->gb) >> 3);
+    if (h->divx_packed) {
+        int current_pos     = s->gb.buffer == h->bitstream_buffer ? 0 : (get_bits_count(&s->gb) >> 3);
         int startcode_found = 0;
 
         if (buf_size - current_pos > 7) {
@@ -3511,16 +3512,16 @@ int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
                        "Consider using the mpeg4_unpack_bframes bitstream filter without encoding but stream copy to fix it.\n");
                 ctx->showed_packed_warning = 1;
             }
-            av_fast_padded_malloc(&s->bitstream_buffer,
-                           &s->allocated_bitstream_buffer_size,
+            av_fast_padded_malloc(&h->bitstream_buffer,
+                           &h->allocated_bitstream_buffer_size,
                            buf_size - current_pos);
-            if (!s->bitstream_buffer) {
-                s->bitstream_buffer_size = 0;
+            if (!h->bitstream_buffer) {
+                h->bitstream_buffer_size = 0;
                 return AVERROR(ENOMEM);
             }
-            memcpy(s->bitstream_buffer, buf + current_pos,
+            memcpy(h->bitstream_buffer, buf + current_pos,
                    buf_size - current_pos);
-            s->bitstream_buffer_size = buf_size - current_pos;
+            h->bitstream_buffer_size = buf_size - current_pos;
         }
     }
 
@@ -3532,7 +3533,9 @@ static int mpeg4_update_thread_context(AVCodecContext *dst,
                                        const AVCodecContext *src)
 {
     Mpeg4DecContext *s = dst->priv_data;
+    H263DecContext *const h = &s->h;
     const Mpeg4DecContext *s1 = src->priv_data;
+    const H263DecContext *const h1 = &s1->h;
     int init = s->h.m.context_initialized;
 
     int ret = ff_mpeg_update_thread_context(dst, src);
@@ -3565,6 +3568,26 @@ static int mpeg4_update_thread_context(AVCodecContext *dst,
     s->cplx_estimation_trash_b   = s1->cplx_estimation_trash_b;
     s->rgb                       = s1->rgb;
 
+    // DivX handling (doesn't work)
+    h->divx_packed               = h1->divx_packed;
+    if (h1->bitstream_buffer) {
+        if (h1->bitstream_buffer_size +
+            AV_INPUT_BUFFER_PADDING_SIZE > h->allocated_bitstream_buffer_size) {
+            av_fast_malloc(&h->bitstream_buffer,
+                           &h->allocated_bitstream_buffer_size,
+                           h1->allocated_bitstream_buffer_size);
+            if (!h->bitstream_buffer) {
+                h->bitstream_buffer_size = 0;
+                return AVERROR(ENOMEM);
+            }
+        }
+        h->bitstream_buffer_size = h1->bitstream_buffer_size;
+        memcpy(h->bitstream_buffer, h1->bitstream_buffer,
+               h1->bitstream_buffer_size);
+        memset(h->bitstream_buffer + h->bitstream_buffer_size, 0,
+               AV_INPUT_BUFFER_PADDING_SIZE);
+    }
+
     memcpy(s->sprite_shift, s1->sprite_shift, sizeof(s1->sprite_shift));
     memcpy(s->sprite_traj,  s1->sprite_traj,  sizeof(s1->sprite_traj));
 
@@ -3577,16 +3600,25 @@ static int mpeg4_update_thread_context(AVCodecContext *dst,
 static int mpeg4_update_thread_context_for_user(AVCodecContext *dst,
                                                 const AVCodecContext *src)
 {
-    MPVMainDecContext *const m = dst->priv_data;
-    const MPVMainDecContext *const m1 = src->priv_data;
+    Mpeg4DecContext *const ctx = dst->priv_data;
+    const Mpeg4DecContext *const ctx1 = src->priv_data;
 
-    m->s.quarter_sample = m1->s.quarter_sample;
-    m->s.divx_packed    = m1->s.divx_packed;
+    ctx->h.m.s.quarter_sample = ctx1->h.m.s.quarter_sample;
+    ctx->h.divx_packed        = ctx1->h.divx_packed;
 
     return 0;
 }
 #endif
 
+static void mpeg4_flush(AVCodecContext *avctx)
+{
+    Mpeg4DecContext *const ctx = avctx->priv_data;
+    H263DecContext *const h = &ctx->h;
+
+    h->bitstream_buffer_size = 0;
+    ff_mpeg_flush(avctx);
+}
+
 static av_cold void mpeg4_init_static(void)
 {
     static uint8_t mpeg4_rvlc_rl_tables[2][2][2 * MAX_RUN + MAX_LEVEL + 3];
@@ -3663,11 +3695,11 @@ static av_cold int decode_init(AVCodecContext *avctx)
     return 0;
 }
 
-#define OFFSET(x) offsetof(MPVMainDecContext, s.x)
+#define OFFSET(x) offsetof(Mpeg4DecContext, x)
 #define FLAGS AV_OPT_FLAG_EXPORT | AV_OPT_FLAG_READONLY
 static const AVOption mpeg4_options[] = {
-    {"quarter_sample", "1/4 subpel MC", OFFSET(quarter_sample), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS},
-    {"divx_packed", "divx style packed b frames", OFFSET(divx_packed), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS},
+    {"quarter_sample", "1/4 subpel MC", OFFSET(h.m.s.quarter_sample), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS},
+    {"divx_packed", "divx style packed b frames", OFFSET(h.divx_packed), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS},
     {NULL}
 };
 
@@ -3694,7 +3726,7 @@ const AVCodec ff_mpeg4_decoder = {
                              AV_CODEC_CAP_DELAY | AV_CODEC_CAP_FRAME_THREADS,
     .caps_internal         = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM |
                              FF_CODEC_CAP_ALLOCATE_PROGRESS,
-    .flush                 = ff_mpeg_flush,
+    .flush                 = mpeg4_flush,
     .max_lowres            = 3,
     .pix_fmts              = ff_h263_hwaccel_pixfmt_list_420,
     .profiles              = NULL_IF_CONFIG_SMALL(ff_mpeg4_video_profiles),
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index d0fbdaf1b4..1ee8e7458b 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -643,8 +643,6 @@ static void clear_context(MPVMainContext *m)
     s->sc.obmc_scratchpad = NULL;
 
 
-    s->bitstream_buffer = NULL;
-    s->allocated_bitstream_buffer_size = 0;
     for (int i = 0; i < 2; i++)
         for (int j = 0; j < 2; j++)
             s->p_field_mv_table[i][j] = NULL;
@@ -792,9 +790,6 @@ void ff_mpv_common_end(MPVMainContext *m)
     s->parse_context.buffer_size = 0;
 #endif
 
-    av_freep(&s->bitstream_buffer);
-    s->allocated_bitstream_buffer_size = 0;
-
     if (!s->avctx)
         return;
 
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index 8697f0108c..2b5267f1c3 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -339,12 +339,6 @@ typedef struct MPVContext {
     int mpeg_quant;
     int padding_bug_score;             ///< used to detect the VERY common padding bug in MPEG-4
 
-    /* divx specific, used to workaround (many) bugs in divx5 */
-    int divx_packed;
-    uint8_t *bitstream_buffer; //Divx 5.01 puts several frames in a single one, this is used to reorder them
-    int bitstream_buffer_size;
-    unsigned int allocated_bitstream_buffer_size;
-
     /* RV10 specific */
     int rv10_version; ///< RV10 version: 0 or 3
     int rv10_first_dc_coded[3];
diff --git a/libavcodec/mpegvideo_dec.c b/libavcodec/mpegvideo_dec.c
index 8f3c401aff..7bbae2fa47 100644
--- a/libavcodec/mpegvideo_dec.c
+++ b/libavcodec/mpegvideo_dec.c
@@ -77,8 +77,6 @@ int ff_mpeg_update_thread_context(AVCodecContext *dst,
         s->current_picture_ptr   = NULL;
         s->next_picture_ptr      = NULL;
         s->last_picture_ptr      = NULL;
-        s->bitstream_buffer      = NULL;
-        s->bitstream_buffer_size = s->allocated_bitstream_buffer_size = 0;
 
         if (m1->context_initialized) {
 //             s->picture_range_start  += MAX_PICTURE_COUNT;
@@ -154,27 +152,6 @@ do {\
     s->low_delay    = s1->low_delay;
     s->droppable    = s1->droppable;
 
-    // DivX handling (doesn't work)
-    s->divx_packed  = s1->divx_packed;
-
-    if (s1->bitstream_buffer) {
-        if (s1->bitstream_buffer_size +
-            AV_INPUT_BUFFER_PADDING_SIZE > s->allocated_bitstream_buffer_size) {
-            av_fast_malloc(&s->bitstream_buffer,
-                           &s->allocated_bitstream_buffer_size,
-                           s1->allocated_bitstream_buffer_size);
-            if (!s->bitstream_buffer) {
-                s->bitstream_buffer_size = 0;
-                return AVERROR(ENOMEM);
-            }
-        }
-        s->bitstream_buffer_size = s1->bitstream_buffer_size;
-        memcpy(s->bitstream_buffer, s1->bitstream_buffer,
-               s1->bitstream_buffer_size);
-        memset(s->bitstream_buffer + s->bitstream_buffer_size, 0,
-               AV_INPUT_BUFFER_PADDING_SIZE);
-    }
-
     // linesize-dependent scratch buffer allocation
     if (!s->sc.edge_emu_buffer)
         if (s1->linesize) {
@@ -585,7 +562,6 @@ void ff_mpeg_flush(AVCodecContext *avctx)
     s->parse_context.index = 0;
     s->parse_context.last_index = 0;
 #endif
-    s->bitstream_buffer_size = 0;
     s->pp_time = 0;
 }
 
diff --git a/libavcodec/nvdec_mpeg4.c b/libavcodec/nvdec_mpeg4.c
index 6d5ac8cd07..61e9900c32 100644
--- a/libavcodec/nvdec_mpeg4.c
+++ b/libavcodec/nvdec_mpeg4.c
@@ -71,7 +71,7 @@ static int nvdec_mpeg4_start_frame(AVCodecContext *avctx, const uint8_t *buffer,
             .quant_type                   = s->mpeg_quant,
             .quarter_sample               = s->quarter_sample,
             .short_video_header           = avctx->codec->id == AV_CODEC_ID_H263,
-            .divx_flags                   = s->divx_packed ? 5 : 0,
+            .divx_flags                   = m->h.divx_packed ? 5 : 0,
 
             .vop_coding_type              = s->pict_type - AV_PICTURE_TYPE_I,
             .vop_coded                    = 1,
-- 
2.32.0



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